First draft.

Add basic core features:
* Authentication: Will use OAuth by deafult. The user will only need to
do an setup process to get his client_passphrase.
* Users: implemented the methods CREATE, UPDATE, FETCH
* Test: add specs for the Users and Clients

I will now start implementing all the other methods.
Add Wallet.

Add Wallets specs and resources.
Transaction support + refactoring

Remove RestClient references
Add filters to http_calls
Add Transaction resources and tests
Refactor the rspec lets and move them to a shared set of resources
Add Bank Details

Add BankDetails resource and test.
Update the create http calls to accept ids.
Add PayIn + Refactoring

Add PayIn resources + tests
Remove debug flags
Remove unnecessary call to self
Improve Client test suite

The client test suite now test for the following cases:
- Create a new client (using a random client id)
- ClientID too long
- Existing ClientID
Add Payout + Refactoring

- Add Payout Ressource + partial tests
- Some minor refactorings
Add Transfers.

Add Transfers resources and tests.
Remove rest_client.

Remove the rest_client gem since it's not required anymore.
PayIn Web Card are now fully tested.

- Add capybara and capybara-webkit for headless testing of the payin
web card
- Add headless testing to the payin web card to test the filling
process of the payline form
Update Payout spec to test on a wallet with actual funds.

Thanks to the previous commit the Payout spec has been updated to use a
wallet with actual funds on it.
Update Transfer spec to test on a wallet with actual funds.

Thanks to the commit ba6cee27f33b3c96c63a6c6db51744fc818c7c30 the
Transfer spec has been updated to use a wallet with actual funds on it.
Bump version to 3.0.0.beta1
Add mininal rails generator

Add a rails generator that create a config file from the client_id and
client_name inputed
moved to Mangopay in the module name
Require rails generators
remove the namespace and renamte the method to setup
Update preproduction description. chenge the source_root
Update template variable
Add client_id method