Changes gmock's version to 1.6.0 and adds release notes.

CHANGES

+Changes for 1.6.0:
+
+* Compilation is much faster and uses much less memory, especially
+  when the constructor and destructor of a mock class are moved out of
+  the class body.
+* New matchers: Pointwise(), Each().
+* New actions: ReturnPointee() and ReturnRefOfCopy().
+* Project files for Visual Studio 2010.
+* AllOf() and AnyOf() can handle up-to 10 arguments now.
+* Google Mock doctor understands Clang error messages now.
+* SetArgPointee<> now accepts string literals.
+* gmock_gen.py handles storage specifier macros and template return
+  types now.
+* Compatibility fixes.
+* Bug fixes and implementation clean-ups.
+
+Potentially breaking changes:
+
+* The description string for MATCHER*() changes from Python-style
+  interpolation to an ordinary C++ string expression.
+* SetArgumentPointee is deprecated in favor of SetArgPointee.
+* Some non-essential project files for Visual Studio 2005 are removed.
+
 Changes for 1.5.0:
 
  * New feature: Google Mock can be safely used in multi-threaded tests

configure.ac

 m4_include(gtest/m4/acx_pthread.m4)
 
 AC_INIT([Google C++ Mocking Framework],
-        [1.5.0],
+        [1.6.0],
         [googlemock@googlegroups.com],
         [gmock])
 
@@ -101,7 +101,7 @@ AC_ARG_VAR([GTEST_VERSION],
            [The version of Google Test available.])
 HAVE_BUILT_GTEST="no"
 
-GTEST_MIN_VERSION="1.5.0"
+GTEST_MIN_VERSION="1.6.0"
 
 AS_IF([test "x${enable_external_gtest}" = "xyes"],
       [# Begin filling in variables as we are able.