New README.md

@seriousamlqz, @yzhang90, @grosu Please review

@grosu, please assign someone who knows better than me to write the Static Weaving Section: I don't use that option.
Explain all options, not only `-n`.  What is `-v`, version or verbose?  `-d` ?  Also, is `<specification file or dir>` correct?  I mean, if I understand it correctly, you can list a set of MOP files and directories of properties, can't you?  If that is the case, I would just say `<properties>` and then explain in words what properties means.