Make errors during template parsing more useful to users

Currently when there is a problem with a template, whether at validation or runtime at creation/update, the error message gives the users almost no clues about where in the template the problem has happened.

We should note:

- Resource/Parameter/Output in which the problem happened (minimum)
- Line number of YAML
- Original source of YAML (including client side get_file's)

Resources can be noted easily by keeping some context while parsing. Line numbers will require adding a custom composer to yaml, and may be even more difficult with json, I have not looked into it. The original source of everything will require clients to submit more context to the server so the error can have everything needed.