Revert file access mode to 0644.
Merge pull request #1221 from monaka/pr-revert-file-access-mode

Revert file access mode to 0644.
use uint8_t for mrb_bool instead of unsigned int; close #1222
Merge branch 'master' of github.com:mruby/mruby
remove our own prototype for sprintf(); ref #1223
rename mrb_to_id to mrb_obj_to_sym since symbol is nothing to do with identifier in mruby
remove unnecessary intern; access to non-member cause IndexError
the receiver should be included in ancestors even when it's a singleton class
Remove mrb_class_obj_get
ArduinoDue Target Cosmetic Change

small cosmetic change
Cosmetic improvements of mrbgems documentation

Cosmetic improvements of mrbgems documentation
Implement :core parameter for conf.gem
Apply :core parameter to default.gembox
Apply :core parameter to full-core.gembox
Merge pull request #1224 from h2so5/remove-mrb_class_obj_get

Remove mrb_class_obj_get
Merge pull request #1226 from bovi/patch-1

ArduinoDue Target Cosmetic Change
Merge pull request #1227 from bovi/patch-2

Cosmetic improvements of mrbgems documentation
Merge pull request #1228 from bovi/mrbgems-core-gem

Implementation of :core parameter for conf.gem
Merge branch 'master' of github.com:mruby/mruby
Improve Gem::Specification for support of dependencies and requirements