Simplified mrbgem.rake in order to build under Windows
Solved loading of filens on different volumes on windows
Merge branch 'master' of https://github.com/mattn/mruby-require

Conflicts:
	mrbgem.rake
	src/mrb_require.c
Fixed Linux compilation
Reverted mrb_class_get() in defining E_LOAD_ERROR
Raise error even when an absolute path is not found
Merged back from upstream. Fixed bug when requiring missing file.
Upstream version of mrbgem.rake still breaks mxint: reverting back
Merge branch 'master' of https://github.com/mattn/mruby-require into test

Conflicts:
	mrbgem.rake
Edit in rake script: now only gems that are added into master build_config.rb
script AFTER the mruby-require gem are compiled as separate objects. Those included
before it are compiled into the mruby library.
Merge pull request #17 from pbosetti/master

Changed logic for rake file when compiling included gems