Do not get template dir from YAML file

YAML files are only to get static information, not for doing
configuration.
Store opts so that we can access them directly
Refactor parsing of rOCCI templates

- Missing unit tests.
- Sample templates can be found in [1].

[1] https://github.com/EGI-FCTF/rOCCI-server/tree/master/etc/backends/opennebula/fixtures/resource_tpl
fix headers for the generated ldifs

The generated ldif documents had some missing elements, therefore
they could not be used. Try to fix them.
do not use class variables for holding the templates
fix duplicated variable