Cleanup: gathered templates in a single location
Cleanup: Fix template references in templates that we have and Evernote doesn't
Cleanup: Move remaining templates to pootle/templates/

Also moved templates from pootle/templates/common/ to pootle/templates/core/

This gets Pootle working again since the app templates loader was removed in
the previous commit.
Improved JavaScript handling of the captcha

Less hackish, less requests, less duplicated code, cleaner separation of
code and not tightly coupled to the editor.

JavaScript code that makes XHR POST requests will need to pass two special
parameters (`sfn` and `efn`) which are the success and error callback
function names which will be executed once the captcha has been
successfully resolved.

Note that the captcha can now be identified via the HTTP 402 status code
(Payment Required) — the captcha can be considered like a sort of payment
the user needs to make in order to continue further. YouTube also makes
use of the HTTP 402 status code for this purpose.
Moved captcha form into its own module

This will allow us further reuse of the form and its functionality in
other parts of the codebase.
Set captcha question programatically

Improves reusability.
Cleanup: Minor changes to align with Evernote code

This will minimize conflicts when picking the following commits.
Moved `ensure_uri` to the url_helpers module
Cleanup: Use urlresolvers.resolve in captcha middleware

This is a change from https://github.com/evernote/pootle/commit/a76f657
Added `fullname` property to user profiles

Ideally this should be handled at the DB level by having a single
`fullname` field thus removing the culture-specific `first_name` and
`last_name` fields.

Partial pick of evernote@9669c47a.
Ajaxify contact form

Partial pick of evernote@a76f6577.
Use contact form to report string errors

The new form serves both as a way to contact site managers as well as to
report errors with strings from the editor.

This also renders useless the need for a `report_target` field in
`Project` models, so that field has been deleted too, along with its
related functionality.

This, and some other previous commits, fixes evernote#15.

Partial pick of evernote@a76f6577. The rest of the original commit is in
several previous commits.
Refactor contact app to report string errors to project report email if exists

If the project has no report email, then fall back to a global report email.
Cleanup: PEP8 and coding style fixes

Partial pick of evernote@bbb2ffab.
Differentiate between scenarios