Added ability to pass Closure to union statement in query builder

Example:
```php
$users = DB::table('users')->whereNull('last_name')->unio(function($q)
{
	$q->from('users')->whereNull('first_name');
})->get();
```
Rename the merge method to collapse.

Signed-off-by: Jason Lewis <jason.lewis1991@gmail.com>
Add merge method to merge in another array or collection.

Signed-off-by: Jason Lewis <jason.lewis1991@gmail.com>
some updates

shorten code, updated docblocks
Updated readme.

Signed-off-by: Jason Lewis <jason.lewis1991@gmail.com>
Merge branch 'master' of git://github.com/laravel/framework into fix/proper-merge-collections

Conflicts:
	readme.md
Update and rename Html.php to HTML.php

Since the Facade was renamed in `app/config/app.php` on the `laravel/laravel` repo, we should rename the actual file so it is consistent with that of `DB.php`, `URL.php` and the class name respectively.
Creation of the setBaseURL function for Ajax requests

When using pagination in an Ajax request is useful to be able to define the URL to be consider to build the paginate links. By default, in an  Ajax request, it will be consider the Ajax URL to build the paginate links. This is a problem because generally in an Ajax response we do not rebuild the entry HTML page. To resolve this problem, we add to the Paginator class the setBaseURL function to indicate the URL to be consider. With this change we can, for example, proceed in the following way in the context of an Ajax request:

echo ‘<ul>’;
$users = User:where(‘age’, ‘>’, ’18‘)->get();
foreach ($users as $user)
{
	echo ‘<li>’.$user->name.‘</li>’;
}
$users->setBaseUrl(URL::route(‘users_list’));
echo ‘</ul>’;
$users->links();

We can use the function $users->getEnvironment()->setBaseUrl() but we think the previous solution much more simple an elegant.
Merge pull request #1237 from miguelbgouveia/patch-1

Creation of the setBaseURL function for Ajax requests
Cleaning up code. Updating readme.
Set exists to true before firing created method. Fixes #1235.
Update Pluralizer.php

Added a matchCase method to attempt to determine case format and apply it but fallback to default value if not found. Added matchCase to the irregular and inflected return values.
Update SupportPluralizerTest.php

Add tests to support new case 'aware' plural and singular methods.
Update Pluralizer.php

Removed space to trigger rebuild from travis.
Update StoreInterface.php

Minor typo in interface comment
Merge pull request #1248 from helmut/typo-fix

Update StoreInterface.php
Don't set cookie if headers have been sent.
Fix missing select clause on some queries. Closes #1236. Closes #1223.
Fix encryption pad handling. Fixes #1238.
Add "reverse" method to Collection.