Build changes to support dynamic GOPATH when inside a project.

* The Makefile contains a GOPATH pointing to the currentworkspace as well. This means when doing development all the files under `~/code/megam/go` are used.
* During packaging all the files under `~/.go` and `~/<currentpackaging directory>` will be used. If the libraries like `github.com/megamsys/libgo` doesn't exists then it will be downloaded into `~/.go`.

Read the blog entry for more updates http://bit.ly/1pzjBpC