Ready to release gflags 1.6!

* google-gflags: version 1.6
* BUGFIX: Fix a bug where we were leaving out a required $(top_srcdir)
* Fix definition of clstring (jyrki)
* Split up flag declares into its own file (jyrki)
* Add --version support (csilvers)
* Update teh README for gflags with static libs
* Update acx_pthread.m4 for nostdlib
* Change REparseCommandLineFlags to return void (csilvers)
* Some doc typofixes and example augmentation (various)

R=jperkins
DELTA=44  (41 added, 0 deleted, 3 changed)


Revision created by MOE tool push_codebase.
MOE_MIGRATION=2838


git-svn-id: https://gflags.googlecode.com/svn/trunk@56 6586e3c6-dcc4-952a-343f-ff74eb82781d