YAML.load now respects Fixnum and Floats
Updated to compile on VisualStudio2010
Fixed on Windows
Symbols are respected.
Range objects are respected
Update README.md
Added support for File IO, which is automatically enabled if the mrb-io gem is available
Added tests to convert scalars to number types
Revert "forward declaratiopn of some vars in order to compile on Windows"

This reverts commit 7be59d735b5e693bd127a16414ead8c16d471362.

Conflicts:
	src/yaml.c
Added tests to convert scalars to number types
Refactored scalar conversion to Float/Fixnum
Update README.md
Updated README
Merge branch '3'

Conflicts:
	README.md
	src/yaml.c
	test/yaml.rb