Clean up acceptance test execution

Remove a redundant `destroy` command and use `assert_execute` to ensure 0 exit
status.
Ensure directory exists when initializing pool

When writing `PoolStorage` skeletons, ensure the enclosing directory exists.
Add misc files to .gitignore

Bundler artifacts, YARD output, etc.
Extend acceptance testing to status and reload

Ensure that the `status` and `reload` commands continue to work when
auto_network is loaded. Vagrant 1.6.0 introduced some internal changes that
broke `reload`.

Also partially reverts cddc317 by adding back a `vagrant destroy` run in an
`after` block. This is redundant, but ensures everything is cleand up if the
acceptance test fails part of the way through.
Set acceptance IP ranges through environment

This paves the way for running multiple providers under acceptance tests. The
obvious candidate is VMware Fusion, but there are still some kinks to hammer
out.

This patch passes in the IP Address range used during acceptance through the
environment. It also does away with the shared contexts used to set these
variables as they were broken. Instead, variables are set in the top-level
config.
Remove deprecated AutoNetwork mixin

This patch removes the old `auto_network!` method that has been issuing
deprecation warnings for a while.

Closes GH-14.
Rename DefaultPool to Settings

In order to support Vagrant 1.6, we will need a place to store global state.
This patch re-factors the existing `DefaultPool` module into a general
`Settings` module that can fill this role.

Also added YARD docs.
Add validation to the default_pool setting

When assigning a value through `default_pool=`, we now check that it will pass
`IPAddr.new`.

Fixes GH-18.
Better plugin loading for acceptance tests

By loading the `gemspec` inside of the Bundler `:plugins` group, we tap into
the Bundler-based plugin loader shipped with v1.5.4. This is better than using
`require` at the top of the Vagrantfile as it is closer to the way things
execute in reality.

This probably means we won't be able to support running acceptance tests
against 1.4.x and earlier. However, that isn't a great loss as the currently
pined version of `vagrant-spec` won't work with 1.4.x.
Re-organize unit tests

Move unit tests into a separate subdirectory to make room for integration
tests.
Store global pool manager instance in settings

After 1.6, we can no longer rely on the Vagrant Environment instance to persist
plugin-specific state. This means that values set during environment
initialization hooks will not survive to be present for the actions that need
them.

This patch moves the storage of state to the AutoNetwork module its self.

(Also, integration tests. Yey!)

Ref: mitchellh/vagrant#3660
Update LoadPool Action for Vagrant 1.6

As of 1.6, actions called from the `:environment_load` hook no longer have
access to some information. The workaround is to use the `env[:env]` key.

The situation is complicated by the fact that actions called outside of
`:environment_load` may be passed an environment that does not inclue
`env[:env]`. The fix for these situations is to only run the `LoadPool` action
during the `:environment_load` hook.

Ref: mitchellh/vagrant#3701
Merge pull request #20 from Sharpie/fix-1_6-stuff

Fixes for Vagrant 1.6

Fixes GH-17.
Update CHANGELOG and version for 1.0.0.beta2
Set up for testing with Travis CI

Modified the Gemfile to read Vagrant version tag from the environment.
Specifying a version of 'HEAD' will cause the tests to run against the master
branch.

Added a `.travis.yml` file that sets up testing against v1.5.4, v1.6.1 and
HEAD.
Add Travis build badge to README
(maint) Fix yardoc warnings in action_helpers
Add directions for enabling Fusion tests

Add tweaks and instructions to the acceptance suite for running tests against
VMware Fusion. Expand `.gitignore` to include Fusion-related files.
Speed up Travis test times for Vagrant 1.6

Vagrant 1.6 depends on Nokogiri which now compiles its own libxml2 during
installation. Adding `NOKOGIRI_USE_SYSTEM_LIBRARIES=true` to the build
environment makes it skip this step.
Add integration test for filter_networks

Most of the changes in this patch involve creating `vagrant-spec` fixtures that
can support complicated integration tests.

All AutoNetwork actions that fire during envrionment initialization are now
covered by integration tests.