Refactor Deep to have different sub-projects for each data store
Merge branch 'develop' into deep-refactor-different

* develop:
  improved support for mixed case column family names, fixed #6
  Adding addAll method to the Cells object

* renamed deep-core to deep-core-cassandra
* fixed ScalaCassandraEntityRDDTest
renamed deep-core-cassandra to deep-cassandra
renamed deep-core-mongodb to deep-mongodb
Added migration guide from version 0.2.9
added: now it throws an exception instead of returning null
Merge branch 'deep-refactor-different' of github.com:Stratio/stratio-deep into deep-refactor-different
have been erased unnecessary files
have been erased unnecessary files
Updated README.md documentation
* splitter DeepSparkContext into CassandraDeepSparkContext and MongoDeepSparkContext
* renamed DeepJobConfigFactory to ConfigFactory
Merge branch 'deep-refactor-different' of github.com:Stratio/stratio-deep into deep-refactor-different

# By rcrespodelosreyes
# Via rcrespodelosreyes
* 'deep-refactor-different' of github.com:Stratio/stratio-deep:
  have been erased unnecessary files
  added: now it throws an exception instead of returning null

Conflicts:
	deep-commons/src/main/java/com/stratio/deep/context/DeepSparkContext.java
	deep-mongodb/src/test/java/com/stratio/deep/config/GenericConfigFactoryMongoDBTest.java
	deep-mongodb/src/test/java/com/stratio/deep/rdd/mongodb/MongoEntityRDDTest.java
Merged previous refactors with mongo's test changes
Refactored Cassandra specific classes and methods to deep-cassandra
Merge branch 'deep-refactor-different' of github.com:Stratio/stratio-deep into deep-refactor-different
Mongo Cell moved to project deep-mongodb
Additional refactor: moved last database-specific classes from deep-commons to the proper sub-project
added new config methods
added new config methods
Merge branch 'deep-refactor-different' of github.com:Stratio/stratio-deep into deep-refactor-different

Conflicts:
	deep-commons/src/main/java/com/stratio/deep/config/ConfigFactory.java
improved Cells integration