Update .gitignore
More explanations on why vagrant-bindfs
Update examples in README

This closes #9 as this issue originally points a documentation problem.
Fix for the 'uninitialized constant' error will be linked to issue 10.
Compatibility with Vagrant 1.4

Vagrant 1.4 replace the Vagrant::Action::Builtin::NFS middleware with a new Vagrant::Action::Builtin::SyncedFolders.
vagrant-bindfs now detects which of these actions are available and insert its own middleware before the right one.

This fixes #10.
Add Gemfile.lock to .gitignore
Update gemspec and licence
Uniform namespacing of the plugin: no more VagrantBindfs module
Bump to 0.2.3