Use class extending instead of interface implementation
Move core plugins to new plugin method
Fix aligning in plugin skeleton
Add MarkDown to README
Fix bolding and one line break
Fix grammar
Another grammar fix
Merge pull request #28 from hashworks/feature/addMarkupLanguageToREADME

Add MarkDown language to README
Merge pull request #27 from hashworks/core/pluginInterfaceToExtendedClass

Plugins: Use class extending instead of interface implementation
Merge remote-tracking branch 'upstream/master'

Conflicts:
	README