Allow setting properties after instantiation

This release adds support for adding properties after instantiation. Besides from that, we now support php down to 5.3.2 and have travisci integration.

A big thanks to @sergeylukin!

isset and unset is now supported on the stubs

Before this release isset would always return false, even if the stub had the property set. unset would also be unable to unset properties.

This is a bugfix release for #2.

Improved exception and property support

Defined methods respond as properties now.

Exceptions can be configured.

First working commit

v0.1.0

Basic functionality done