improve build scripts (Windows)

- add -Full parameter to Build.ps1 to also get dependencies
- add progress information
- replace $STDataPath with $STPackagesPath

Usage:

1) Set $STPackagesPath to Sublime Text's packages path

In order to find out your packages path:
   a) Open Sublime Text
   b) Open the Python console
   c) Type in sublime.packages_path()<RETURN>

2) Run once ./bin/Build.ps1 -verbose -full

That should grab dependencies and publish a version locally.

3) Subsequently, you can simply invoke the script like this:

    ./bin/Build.ps1 -verbose

In case you'd need to get the dependencies again, just run the
script as in step (3).

Other features of Build.ps1 include:

    -Restart: restarts Sublime Text (sublime_text must be on your
     PATH)
    -Clean: wipes the deployment FSharp target folder
    -Debug: stops execution at predefined stages and prints info