Change release version to 0.8.0
Change release version to 0.8.0

Also add interface for build scripts to query release version.

Change-Id: I2e9e4ae41764ed0fb4a7436dafc2cf28f8aad357

rlugojr/incubator-trafodion,mashengchen/incubator-trafodion,robertamarton/incubator-trafodion,robertamarton/incubator-trafodion,robertamarton/incubator-trafodion,rlugojr/incubator-trafodion,mashengchen/incubator-trafodion,rlugojr/incubator-trafodion,mashengchen/incubator-trafodion,robertamarton/incubator-trafodion,rlugojr/incubator-trafodion,rlugojr/incubator-trafodion,robertamarton/incubator-trafodion,rlugojr/incubator-trafodion,mashengchen/incubator-trafodion,robertamarton/incubator-trafodion,rlugojr/incubator-trafodion,robertamarton/incubator-trafodion,mashengchen/incubator-trafodion,mashengchen/incubator-trafodion,robertamarton/incubator-trafodion,mashengchen/incubator-trafodion,rlugojr/incubator-trafodion,robertamarton/incubator-trafodion,mashengchen/incubator-trafodion,rlugojr/incubator-trafodion,rlugojr/incubator-trafodion,mashengchen/incubator-trafodion,mashengchen/incubator-trafodion,robertamarton/incubator-trafodion