[maven-release-plugin] prepare release gson-1.7
[maven-release-plugin] prepare release gson-1.7

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