* refactor(es6): Upgrade RequireIncludeDependencyParserPlugin to es6 and remove AbstractPlugin dep
* refactor(es6): Upgrade RequireEnsureDependenciesBlockParserPlugin to es6 and remove AbstractPlugin dep
* refactor(es6): Upgrade RequireContextDependencyParserPlugin to es6 and remove AbstractPlugin dep
* refactor(es6): Upgrade HarmonyExportDependencyParserPlugin to es6 and remove AbstractPlugin dep
* refactor(es6): Upgrade HarmonyImportDependencyParserPlugin to es6 and remove AbstractPlugin dep
* Remove AbstractPlugin