Dependendy managment and Vagrant

[Ext3h]

Set of patches which reduces the effort required to set up a working codeface instance.

• Add dependency declarations for node.js and python
• Skip already installed packages in packages.R
• Migrate Travis CI and Vagrant to a common set of scripts

Until now, Vagrant was broken and did fundamentally differ from the provision process used by Travis CI. Now a simple "vagrant up" is sufficient to confirm whether the integration will succeed or not.

Please note that the Travis CI can succeed even if vagrant does not, as Travis will wrongly grant too many write permissions.

E.g. "sudo python2.7 setup.py -q install" will cause the .egg to become write protected and the R scripts will silently fail when attempting to write to the default log directory. This goes unnoticed in Travis CI.

[Ext3h]

And another 3 related patches:

• Work around a bug when running Vagrant on Windows, related to the emulation of symlinks
• Don't polute the root directory with 3rd party software during provision (cppstats and srcML)
• Update .gitignore

I have tested Vagrant on Windows and multiple Linux distributions, using Virtualbox as provider. Integration tests complete on all platforms.

[Ext3h]

Applied all requested changes and submitted to mailing list.