implemented partitioned by column expressions

Conflicts:
	sql/src/main/java/io/crate/analyze/PrimaryKeyVisitor.java
	sql/src/main/java/io/crate/metadata/doc/DocIndexMetaData.java
	sql/src/main/java/io/crate/planner/RowGranularity.java
	sql/src/test/java/io/crate/integrationtests/TransportSQLActionTest.java
	sql/src/test/java/io/crate/metadata/table/TestingTableInfo.java