added Doctrine_Access::__isset() and Doctrine_Access::__unset() for complete support of magic method invocations

New component Doctrine_EventListener_AccessorInvoker for automatic invoking of get* and set* methods

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removing the closing PHP tags form all php files, it\'s not needed and can break sessions which are whitespace sensitive

when using Doctrine::compile(), having the require_once()'s in the source files will break things. This is because the file hasn't been included, but the class has been defined in the compiled file.  This means you have to rely on autoload to allow compile to function (or strip out all require_once's from the code on compile, but atleast one needs to be maintained). IMPORTANT: you MUST now use autoload.

Tests for covering the Doctrine_Collection::loadRelated functionality for basic many-to-many relations