Update README.md

Fixing link to tutorial
Merge pull request #11 from amutz/patch-1

Fix tutorial link in the README
cc.flags is an array rather than a string
Update blog link in README.md
change cflags and ldflags to arrays so as to adapt customization. Fixes #12
Bump gem version
Fix cflags and ldflags setting
Bump submodule versions
Support static linked libs
Bump gem version
Fix gemspec
Bump emscripten version
Fix optimization flag
Bump version again since a lot of bugs are fixed
Compatibility with windows cygwin environment
Update readme containing windows notes
Update submodules
Bump gem version
Bump submodule versions
Build js file first before building mrbtest