Merge branch 'release/0.4.0' into develop
remove non-object oriented interface and tests
rename oo-interface to RangeTracker
rename method names (drop '_oo' suffix)
change Namespace to Number::RangeTracker
cleanup non-oo artifacts
change attribute names: add -> ranges, rm -> remove
add 'units' attribute (default = 1)
add $range->inverse
Fix 'keys on reference is experimental' warnings
Gitignore 'other/'
Update version #
Merge branch 'release/0.5.0'