Abstracting JInstallerAdapter element creation
Merge remote branch 'mbabker/installAbstract' into installAbstract

Conflicts:
	libraries/cms/installer/adapter.php
	libraries/cms/installer/adapter/package.php
Fix regression and improve JInstallerAdapter extension detection
Merge pull request #7 from mahagr/installAbstract

Abstracting JInstallerAdapter element creation