Update the doc for 0.2.8 version.

Changelog.txt

@@ -1,4 +1,16 @@
 OpenBLAS ChangeLog
+====================================================================
+Version 0.2.8
+01-Aug-2013
+common:
+	* Support Open64 5.0. (#266)
+	* Add executable stack markings. (#262, Thank Sébastien Fabbro)
+	* Respect user's LDFLAGS (Thank Sébastien Fabbro)
+
+x86/x86-64:
+	* Rollback bulldozer and piledriver kernels to barcelona kernels (#263)
+	  We will fix the compuational error bug in bulldozer and piledriver kernels.
+
 ====================================================================
 Version 0.2.7
 20-Jul-2013

Makefile.rule

@@ -3,7 +3,7 @@
 #
 
 # This library's version
-VERSION = 0.2.8-rc1
+VERSION = 0.2.8
 
 # If you set the suffix, the library name will be libopenblas_$(LIBNAMESUFFIX).a
 # and libopenblas_$(LIBNAMESUFFIX).so. Meanwhile, the soname in shared library