__FILE__ test: add support for \ as separator

mruby-time: add gettimeofday(2) for Windows

mruby-time: various smaller changes

small refactor in mirb

Change the position of -L option from MRUBY_LIBS to MRUBY_LDFLAGS

remove unused variable

fix mruby command returning EXIT_SUCCESS when program file can't be opened.

GLOBAL_RAND_SEED_KEY is no longer used.

opened.

fix argument spec setting of Kernel.exit method.

this method requires 1 optional argument.

Add existing include/ directory only.

Fix #1803

Add mruby-bin-mruby-config

mruby command should not execute program on "syntax only option(-c)".

fix indent.

fix off-by-one error in attrsym