Add ddg.function and modify ddg.procedure
Merge branch 'master' of https://github.com/blernermhc/RDataTracker
Add ddg.function and modify ddg.procedure
Conflicts:
	R/RDataTracker.R
	examples/checkpointTest/expected_checkpointFileTest.out
	examples/checkpointTest/source_expected_checkpointFileTest.out
	examples/consoleSource/expected_consoleSource_ddg.txt
	examples/consoleSource/source_expected_consoleSource_ddg.txt