No need to specify empty bin list anymore(example)
Merge remote-tracking branch 'upstream/master'
Merge remote-tracking branch 'remotes/mruby/master'
add nil.to_a, nil.to_f, nil.to_i methods
refactor mrb_realloc()

remove the redundant codes with mrb_malloc_simple()
Merge pull request #1318 from Fleurer/refactor_realloc

refactor mrb_realloc() in gc.c
Merge pull request #1304 from iij/pr_nil_methods

add nil.to_a, nil.to_f, nil.to_i methods
Refactor mrb_obj_eq() func in object.c.
Refactor mrb_range_eq() func in range.c.
Merge pull request #1320 from suzukaze/refactor-object-c

Refactor mrb_obj_eq() func in object.c.
Merge pull request #1321 from suzukaze/refactor-range-c

Refactor mrb_range_eq() func in range.c.
Refactor range_eql() func in rangec.c
Add Range#eql? method test.
Fix Range#==
Fix some signed unsigned warnings, int to size_t.
Change int to size_t.
Change int to size_t
Merge pull request #1322 from suzukaze/refactor-range-c

Refactor range_eql() func in rangec.c and add Range#eql? method test.
Merge pull request #1324 from h2so5/fix-range-equal

Fix Range#==
Merge pull request #1325 from carsonmcdonald/unsignedfixes

Fix a few unsigned signed comparison warnings