construction tests for IntervalForest passed
subsetting and coercion implemented and tested for IntervalForest
all IntervalForest unit tests passed
adding new IntervalTree code
fixing NAMESPACE problem after devtools
support Rle factors
Merge branch 'master' into IntervalForest

Conflicts:
	src/IntervalTree.c
findOverlaps-Ranges-IntervalForest-method supports Rle partition
Merge branch 'master' of https://github.com/hcorrada/IRanges
Merge branch 'IntervalForest'