* use https everywhere

* use https links on the files that are left

Also, removed some broken links and updated redirections.

This avoids spawning additional processes as $PWD **always** contains
the current working directory.

This commit allows for paths with spaces to be symlinked
in Pow.

If an application is located in a folder like `/some path/to the/app`
the powit command would fail when it shouldn't. It's not the case
anymore.

add powit command to symlink an app if it hasn't been already

https://gist.github.com/1019777/70dbb46db9bd5b346faf543a9dd4edac4782adda

Add helper function to restart an app running on Pow!