* numeric.c (ruby_float_step): extracted from num_step().
	* range.c (range_step): uses ruby_float_step() for float range.
	  [ruby-dev:37691]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8_7@22528 b2dd03c8-39d4-4d8f-98ff-823fe69b080e