bitCoerce now attempts to coerce given arguments for bitwise operations
into fixnums or bignums, and raises an exception if it is unable to do so.
Numeric#quo now delegates to Rational#quo, which performs conversions according
to MRI behavior.
Update Numeric#step to be 2.2 compliant

Including support for kwargs and better infinite bounds handling.

To support this change, ArgsUtil.extractKeywordArgs has been added
which will validate kwargs and extract an array of values given a list
of keywords to accept. This should probably be rolled into the
@JRubyMethod decorator at some point so that kwargs validation and extraction
is transparent.
Merge pull request #2176 from cheald/num_fixes

Numeric fixes