Refactor using() method to throw an exception

Add ProviderNotRegistered exception
Huge refactoring

* Add new Result classes (Address, Bounds, Region, Country, County,
  Coordinates)
* Refactor dumpers (remove Interface suffix, define a new method
  signature)
* Remove Interface and Exception suffixes
* Rename properties such as:
    - city => locality
    - cityDistrict => subLocality
    - zipcode => postalCode
* Remove `autoload.php`
* Reintroduce string formatting into the `AddressFactory`

Refs #345
Fix exceptions, remove RuntimeException
Remove 'Dumper' suffix
Rework ProviderBasedGeocoder
Rewrite README
Remove useless file
Update CHANGELOG
Make ProviderBasedGeocoder extendable
Update travis-ci config

remove PHP 5.3 support
Fix doc
Move Result classes to the Model sub-namespace

and update code base accordingly
Fix failing test
Rename ArcGISOnline provider class
Fix various phpdoc issues
Rename all providers by removing the Provider suffix
Merge pull request #350 from geocoder-php/refactoring

[RFC] Refactoring for #345