providers/docker: choose proper provider for host VM
Add colorization and log_level support to salt provisioner.

This commit adds two new options to the salt provisioner:

- `colorize`: controls color output. Defaults to no-color (present behavior).
- `log_level`: controls log level. Defaults to `debug` (present behavior).

Docs included!
Merge pull request #3603 from eykd/feature/colorize-salt-output

provisioner/salt: Add colorization and log_level support to salt provisioner.
website/docs: update slat docs
Update CHANGELOG
website/docs: Add missing `end` to "Run Once or Always" example
website/docs: Fix link to global-status command
fix chef version checking

the version checking here uses a function which is intended only
for chef cookbook versions, which must be x.y or x.y.z.  when fed
a legal chef prerelease version the prior code throws an exception:

[2014-05-01T22:08:01+00:00] FATAL: Configuration error Chef::Exceptions::InvalidCookbookVersion: '11.14.0.alpha.1' does not match 'x.y.z' or 'x.y'
[2014-05-01T22:08:01+00:00] FATAL:   /tmp/vagrant-chef-2/solo.rb:6:in `from_string'
[2014-05-01T22:08:01+00:00] FATAL: Aborting due to error in '/tmp/vagrant-chef-2/solo.rb'

since we only need to compare the major and minor version numbers a
simple #to_f sufficies for this test.

alternative, we could use Gem::Version here, but i didn't really see
the need to...
remove require
Merge pull request #3604 from lamont-granquist/lcg/fix-prerelease-versions

fix chef version checking
Update CHANGELOG
fix "maintiner" typo
Merge pull request #3607 from aspiers/maintiner-typo

fix "maintiner" typo
core: Allow insecure RubyGems for plugins [GH-3610]
website/docs: don't need a static IP for NFS [GH-3608]
providers/virtualbox: remove old print
Update net-ssh dep [GH-3605]
communicators/ssh: detect if config.ssh.shell is non-functional [GH-3040]