Eliminate the use of xtend in compatibility/sal-compatibility

The following xtend files need to be converted to java. This will save build time and also provide us clean code thus making it easier to read and debug,

• ComponentActivator.xtend
• DataPacketAdapter.xtend
• FlowProgrammerAdapter.xtend
• InventoryAndReadAdapter.xtend
• MDFlowMapping.xtend
• TopologyAdapter.xtend
• TopologyCommitHandler.xtend
• TopologyMapping.xtend
• TopologyProvider.xtend
• TopologyTransaction.xtend

Also cleanup all the xtend dependencies from the pom.