Allow specifying of doctrine template implementations, closes #786
merge 8e6bcc947761b5e53c7931504d249e82da3cfcb0 to 82da6ba628f647e4811f8cba6c2c3cbd0de0237c (from 0.11)
made _common.xsl more modular, with callable templates for migrating elements to new namespcaes and separate templates for each envelope element
fixed copy/paste mistake in 8cdc60fe7bdd05d56720076fc0ee7e2e7cd61630
fixed copy/paste errors in comments