Fix two :iteration bugs

- Make sure the component only resolves template properties targeting
  itself.
- Stop resolving template properties if they're not alias.

The first one solves an issue where @a:iteration and @b:iteration would
both be solved to the same object.
The second solves the issue of not resolving @a:iteration if "a" happened
to have an alias of :iteration to another @a:iteration.
Fix repetition specs failing at random

We now check if the inner repetition needs to draw or not and act
accordingly.
Merge pull request #1435 from aadsm/fix-iteration

Fix iteration