SGF-140 - Update to Spring Data Commons 1.5.0.

Expose GemfireMappingContext to the parent class to enable PersistentEntity lookup.
merge 1.2.2
Merge pull request #21 from olivergierke/SGF-140

SGF-140 - Update to Spring Data Commons 1.5.0.
Merge branch 'master' of github.com:SpringSource/spring-gemfire
renaming classes, etc
DATACMNS-260 removed setSpElEvaluator call from MappingPdxSerializer
removed setSpELEvaluator from MappingPDXSerializer for commons 1.5 change
SGF-145 - allow disk overflow with non persistent regions
merged MappingPDXSerializer with master
SGF-146 - improved test performance
Fixed bad import which broke CI build
Integrated GemfireTestRunner