update to Ruby 2.0, DevKit 4.7.2, Omnibus Chef 11.10.4 (in favor of chef...

... gem install), Git 1.9, ConEmu 140304, etc. (see CHANGELOG)

Various updates to tools and gems:
 * tool updates:
  * update to Vagrant 1.3.5
  * update to Ruby (x64) 2.0.0-p451
  * update to Omnibus Chef 11.10.4 (in favor of gem install)
  * update to DevKit (x64) 4.7.2
  * update to ConEmu 140304
  * update to PortableGit 1.9.0-preview
  * update to KDiff3 (x64) 0.9.97
  * update to putty 0.63
  * remove hostsedit (unused leftover)
 * gem updates:
  * update to bundler 1.5.3
  * remove pre-installed chef gem in favor of Omnibus Chef
  * install knife-audit and knife-server to Omnibus embedded Ruby

Most notably is the update to Omnibus Chef. Previously Chef was installed as a gem to the system Ruby, as of this PR Chef is installed the Omnibus installer which comes with its own embedded Ruby. This also means that knife plugins are now installed to the Omnibus embedded Ruby rather than system Ruby.

An update to Vagrant 1.4.3 had been considered but will be deferred until there is an alternative to fgrehm/bindler that is compatible with Vagrant >= 1.4. Since Vagrant 1.5 [will use bundler internally](https://github.com/mitchellh/vagrant/pull/2769) we probably have to wait until bundler is exposed for vagrant plugin management. Until then we stick with Vagrant 1.3.5 since bindler support is essential.

This should fix #42 as well.