[TASK] Allow migration of rte media tags that are stored as &lt;media

Conflicts:
	Classes/Service/MigrateRteMediaTagService.php
Merge pull request #49 from MaxServ/issue-47

[TASK] Allow migration of rte media tags that are stored as &lt;media
Merge pull request #48 from eqipe/master

Added handling of dam_pages in MigrateRelationsService.
[TASK] Allow media tags without target, class or title
Merge pull request #50 from MaxServ/issue-19

[TASK] Allow media tags without target, class or title