Test VM provisioning refinements

- [x] Clean up gradle dependencies from Cheffile.lock by regenerating it
- [x] Set non-empty root passwords for mysql (empty ones don't work with newer versions of mysql cookbook)
- [x] Switch jdk version to 1.7 to match the one used by Travis-CI (current implicit version is 1.6)
- [x] Auto-provision chef via [vagrant-omnibus](https://github.com/schisamo/vagrant-omnibus)
- [x] Re-use official [Swap LWRP cookbook](https://github.com/sethvargo-cookbooks/swap) for swap file creation (instead of custom script)
- [x] Refactor Vagrantfile to version "2"
- [x] Setup Oracle XE if relevant setup package is in project root dir
- [x] Change to a CentOS 6.5 box
- [x] Use git directly as recipe (less risk of non-exact package name like git-core instead of git). Also switch it to compile it from source - this allows better control on git version.
- [x] pin git version in Vagrantfile
- [x] postgresql - seems the hacks to handle dependencies by compile-time install of recipes are not needed any more (fixed upstream). Needs another little tweak but I have patch for it.
- [x] postgresql - remove hardcoded paths and package names from Vagrant (defaults are good enough)
- [x] change postgresql version to 9.3
- [x] Consider setting memory and maybe other machine settings in Vagrantfile (public boxes are sometimes configured with too small amount of RAM; or too much)
- [x] Change vagrant box name from `centos` to something more descriptive (e.g. `dbfitvm-test`)