dev: Clean up implementation, remove dead code

Remove unused code and outdated comments, and simplify / update
to take advantage of features in python 2.6+.
cibconfig: Better error when referring to non-existant template
high: cibconfig: Support rules in attribute lists (bnc#865292)

This patch rewrites much of cibconfig to remove the list
intermediary format previously used when parsing. This was
done to enable rule expressions in nvset lists wherever
Pacemaker allows such expressions.

Also fixes a number of issues discovered while implementing
this change, and simplifies some of the CLI syntax:

* Use 'in' and 'spec' instead of 'in_range' and 'date_spec'. The
  old syntax is still allowed and translated into the new form.

* Don't display $id=... unless necessary (there are multiple
  instances on the same level or someone refers to that item by id).

* Fall back to assuming that the pacemaker version is >= 1.1.8
  if version detection fails.

* Fixes issues with handling resource tags