[maven-release-plugin] prepare release gson-2.3
[maven-release-plugin] prepare release gson-2.3

mbrukman/gson,DanySK/gson-extras,todoooo/gson,testcenter/gson,testcenter/gson,google/gson,todoooo/gson,todoooo/gson,testcenter/gson,mbrukman/gson,DanySK/gson-extras,gv2011/jsoncore,mbrukman/gson,DanySK/gson-extras