Simplify mrb_range_beg_len(). Don't use OTHER macro.
Clean code up.
Return nil if argument of NODE_RETURN and NODE_NEXT is not specified.
Increase TEST_INFINITE_RECURSION_MAX value from 100000 to 1000000 because modification of handling of `NODE_RETURN` reduces stack size.
Modify stack position of NODE_DEF and NODE_SDEF.
Merge pull request #895 from monaka/pr-code-cleanup-20130226

Clean code up.
Merge pull request #898 from masamitsu-murase/modify_return_value

Modify handling of NODE_RETURN and NODE_NEXT.
Merge pull request #893 from monaka/pr-simplify-mrb_range_beg_len

Simplify mrb_range_beg_len(). Don't use OTHER macro.
Merge pull request #899 from masamitsu-murase/modify_stack_position_of_method

Modify stack position of NODE_DEF and NODE_SDEF.