merge revision(s) r45858,r45859,r45860,r45861,r46638: [Backport #9811]

	numeric.c: indent

	* numeric.c (ruby_num_interval_step_size): adjust indent.
	* numeric.c (num_step_scan_args): check keyword arguments and fail
	  if they conflict with positional arguments.
	  [ruby-dev:48177] [Bug #9811]

	* numeric.c (num_step_scan_args): table argument of rb_get_kwargs() is
	  array of IDs, not Symbols. [ruby-dev:48353] [Bug #9811]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_1@46661 b2dd03c8-39d4-4d8f-98ff-823fe69b080e