Tool updates again

Merge in all tool updates:

 * update to vagrant-cachier 1.1.0 (and remove earlier workaround for [fgrehm/vagrant-cachier#113])
 * update to vagrant-berkshelf 3.0.1
 * update to vagrant 1.6.5
 * update to ChefDK 0.3.5
 * update to PortableGit 1.9.4-preview20140929
 * update to ConEmu 141110

Also add ChefDK specific fixes:

 * fix path to ruby.exe in .bat files so ChefDK can live outside of `C:\opscode` (see [opscode/chef-dk#68](https://github.com/opscode/chef-dk/issues/68))
 * ensure that gems are always installed in the ChefDK embedded Ruby, not in `$HOME/.chefdk`
 * downgrade to bundler 1.6.7 for [compatibility with Vagrant 1.6.5](https://github.com/opscode/chef-dk/issues/218#issuecomment-63271238)