Add logic to embed resources into DOCX package.

major change:
1. Now these functions work with resources parameter.
- wpml/content-types-xml
- wpml/word-rels-document-xml-rels

2. Resources data can be created by
- wpml/make-resources

TODO:
- Embed body(binary data) of the resources into DOCX package.
Merge branch 'master' of https://github.com/bakyeono/litedocx