Automatically instantiate aliased container templates

[HertzDevil]

This PR adds support for two kinds of aliases:

• Aliased names inside template type arguments, e.g. QVector<QRgb> now resolves properly to QVector<unsigned int>. Both C++ types will use the same wrapper, so the former container is no longer instantiated separately, as required by Generic pseudo-instantiation macro for container wrapper types #102.
• Aliases to container instantiations, e.g. QObjectList now resolves properly to QList<QObject *>. Consequently, the wrapper for QObject::children() will no longer return a raw pointer to the container after this PR, as long as the appropriate alias is defined in the config file:

  types:
    QObjectList: { alias_for: "QList<QObject *>" }

Due to recent changes, the type database now has separate rule entries for actual C++ containers (e.g. QList<QWindow *>) and their template-less aliases (e.g. Container_QList_QWindow_X_). This shouldn't affect any existing bindings; in particular, typedefs in the C++ wrappers are unaffected because they are populated by Graph::Alias instead.

[Papierkorb]

Thanks!