Allow to provide parameters for PullRequests list

According to the [API documentation](https://developer.github.com/v3/pulls/#list-pull-requests) of the v3 API a sort can be added and some other parameters not yet supported by this library. I have changed the "all" function to allow parameters to be given.
Update composer.json
Fix tests and add defaults
Also fix the actual tests since it requires an array now
Tabs vs spaces, missing )
Merge pull request #137 from GrahamCampbell/patch-1

Update composer.json
Removed double header from a request
Merge pull request #140 from lyrixx/double-header

Removed double header from a request
Corrected repository hooks documentation link
Merge pull request #147 from WyriHaximus/patch-1

Corrected repository hooks documentation link
Merge pull request #136 from syphernl/patch-1

Allow to provide parameters for PullRequests list
Added classes, tests, and documentation for GitHub Enterprise.
Added enterprise and the "ent" alias to list of valid APIs.
Merge pull request #148 from guillermoandrae/master

Added GitHub Enterprise classes, tests, and documentation.
added User::organizations, to be able fetch user's organizations
added test for User::organizations
Merge pull request #152 from KnpLabs/add-userapi-organizations-call

added User::organizations, to be able fetch user's organizations
Added missing sort options on user repositories fetch

Fixed cs
Merge pull request #141 from Nek-/feature/new-github-filter-options

Added missing sort options on user repositories fetch
Add support to get all milestones.

The GitHub API allows you to retrieve open, closed, or all milestones.
Add support to retrieve all milestones in addition to just the open or
the closed ones.