Readme Update

While moving TeamCity to a new machine I went through the read me to install and found a few issues which I fixed:
- Link for Mac Qt download was not working
- There was a link for installing Mac Qt which was about installing from source, when the instructions install from build package. Removed.
- Ubuntu instructions were missing libudev-dev (not sure about Fedora?)
- Updated Windows instructions to be more specific to VS 2010 and included links directly to the downloads you need for that.
- Removed mingw comment for Windows since that is no longer in the build system.

After this goes in. I'll test all the links.