Refactoring Comparable
Merge pull request #2128 from mirichi/refactoring-comparable

Refactoring Comparable
mruby-string-utf8: use mrb_int instead of size_t
revert 3644f1b temporary since it caused SEGV only on Travis-CI
Refactor flo_finite_p()
Refactor fix_and()
Refactor fix_or()
Refactor fix_xor()
Merge pull request #2130 from suzukaze/refactor-numeric.c

Refactor numeric.c
check length before calling stack_copy(); based on a patch from @mirich; close #2129
Merge branch 'master' of github.com:mruby/mruby
bit more peephole optimization for NODE_LVAR
The correct is to compare the MRB_STACK_GROWTH.
Define eval as module function.
Class.constants to take optional argument; close #2133
Merge pull request #2135 from mirichi/bug-fix

correct to compare MRB_STACK_GROWTH.
Merge pull request #2137 from take-cheeze/module_function_eval

Define eval as module function.
mark may be missed when eval() is called
forgot to remove abort()
re-apply 3644f1b since we have fixed GC bug