2018.04.18: version 3.0
	 - Upgraded libslink to handle IPv6

2017.01.26: version 2.9
    - Added MseedRing command to redirect/echo output in miniSEED format in
    an alternate/additional ring (depending on WriteMSEED setting)

2016.10.17: version 2.8
	- Update libslink to version 2.6.
	- from libslink: Always send packet time with request if available.
	- from libslink: Improved support for building on Windows.

2015.5.1: version 2.7
	- Use slp_dtime() instead of gettimeofday() in MaxRate logic handling
	to increase portability.

2013.12.16: version 2.6
	- Update libslink to version 2.4b.
	- Remove logic that tested SeedLink packet types and instead forward
	all received packets, converting any records with a positive sample
	count and non-zero sample rate to TRACEBUFs.

2013.8.29: version 2.5
	- Fix parsing of MaxRate option, thanks P. Lombard.

2013.7.10: still version 2.4
	- Only lookup the TYPE_MSEED value when the WriteMSEED option is used
	to be more backwards compatible, suggested by Paul F.
	- Remove embedded NULL (\0) in ring status messages, avoid compiler
	warnings.

2013.7.6: version 2.4
	- Fix parsing of StateFile option, recognize '#' as start of comment.
	- Add 'WriteMSEED' parameter file option to allow forwarding the
	received miniSEED records directly to the transport ring as TYPE_MSEED 
	messages instead of creating TYPE_TRACEBUF2 messages.
	- Use libmseed for parsing miniSEED records instead of the limited
	routines included with libslink.  This allows support for more encoding
	types (e.g. 32-bit and 64-bit floats).
	- Remove support for creating tracebuf1 messages, the 'ForceTraceBuf1'
	option is no longer recognized.
	- Replace nanosleep() with portable slp_usleep() included in libslink
	and remove WINNT declarations.

2012.5.31: version 2.3
	- Update libslink to version 2.4.
	- Incorportate patch from Jacob Crummey which adds a new SLRecSize
	option to specify the SEED record size expected from the server.
	A 512-byte record is the default for SeedLink, this option is only
	for supporting specialized SeedLink servers that generate alternate
	record lengths such as 256 or 128 bytes.
	
2012.5.8: version 2.2
	- Allow StateFile parameter to be specified with an optional
	file name to explicity be used for the state file instead of
	generating a file name and putting it into the EW_PARAMS dir.

2011.06.08: version 2.1.1
	- made able to compile on Windows, tested there too - Paul Friberg/Stefan Lisowski

2010.12.1: version 2.1
	- Add instId parameter to override the Installation ID
	included in TraceBuf packets.  By default this is determined
	for the local installation defined by EW_INSTALLATION.

2010.10.8:
	- Update to libslink 2.3.
	- Add MaxRate parameter to limit rate in bytes/second, thanks to
	Victor Kress for initial implementation.
	- Fix check for _WINNT instead of _INTEL when creating the
	state file name, thanks Eric Haug.

2008.3.18: version 2.0
	- Update to libslink 2.2 including fixes for compiling for Win32.

2008.3.5: version 2.0pre
	- Update to libslink 2.1 including support for wildcard network
	and station codes with SeedLink servers that support this extension.
	- Check for parse/unpack errors in mseed2ewring(), log message
	and continue operation, thanks to Matteo Quintiliani.

2006.4.3: version 1.4.1
	- Add a compile time check for TRACEBUF2 messages when running
	the GetType() function for that type.  This should suppress a
	message from the EW libraries that the type doesn't exist but
	otherwise has no operational effect.

2006.3.7: version 1.4
	- Fix parsing of Stream definition (NET_STA) for single
	character network codes.

2006.1.27: version 1.3
	- Update to libslink 1.6 including minor bug fixes.

2005.7.14: version 1.2.2
	- Fix the forcetracebuf logic so the correct message type
	is used when the trace buf type is forced.

2005.4.15: version 1.2.1
	- Fix some uninitialized variables and compiler warnings.

2005.4.14: version 1.2
	- Implement a progressive throttling mechanism on the main loop
	to fix data collection with high data rates.  The previous
	throttling was too agressive and would not allow the TCP buffers
	to be cleared fast enough.

2005.4.13: version 1.1
	- Add comments to the documentation about maximum expected
	TRACEBUF message size.
	- Update to libslink 1.5.

2005.4.12: version 1.1pre3
	- Fix comparison of non-NULL terminated string in mseed2ewring.
	Thanks Jim Luetgert.

2005.4.8: version 1.1pre2
	- Add capability to create TRACEBUF2 messages on systems
	that support them.  TRACEBUF2 messages include location codes.
	- Add 'ForceTraceBuf1' config option to force the creation of
	TRACEBUF messages on systems that support TRACEBUF2.

2005.4.7: version 1.1pre1
	- Update to libslink 1.5pre2.

2004.1.21: version 1.0
	- Add StateFileInt option.
	- Update to libslink 1.0.

2003.8.13: version 0.9.6
	- Remove some unnecessary variables and #include <time.h>.
	- Cleanup NT makefile.

2003.8.12: version 0.9.5
	- Cleanup and (hopefully) simplify the module configuration code,
	removing the need for the interlaced parameter structures.  Most
	of the parameters were moved to global variables.
	- Changed the 'StateFile' configuration parameter to a boolean
	flag, the filename is 'slink<mod id>.state' and placed in the 
	parameter directory indicated with the EW_PARAMS environment
	variable.  Less flexible but easier for the user.
	- Use the current logging scheme, writing a log file during init
	no matter what the logging level.
	- Rename parameters: MyModId -> MyModuleId, OutRing -> RingName
	- Update to libslink 0.9.

mid-2003: version 0.9.1
	- Initial version based on liss2ew sources.
