Fail unit submission if fuzzy flag is set

Unless users have administration privileges, now they're required to clear
the fuzzy flag.

This covers the backend side of evernote/pootle#157.

Conflicts:
	pootle/apps/pootle_store/forms.py
Require non-admin users to always clear the fuzzy flag

Non-admin users now have the fuzzy checkbox disabled by default. It'll be
shown if the initial state of the unit is fuzzy or some other action (MT
translation, auto-translation etc.) turned the unit into fuzzy state.

Whenever the fuzzy checkbox is displayed for non-admins, they are forced
to clear it, otherwise the submit button won't be enabled.

This covers the frontend side of evernote/pootle#157.
Django 1.5: fixed `UnitStateField` behavior

The interpretation of values changed in the templates and the field now is
getting values other than strings as well (`True`, `False` and `None`).

Conflicts:
	tests/forms/unit.py
Partial pick: Arbitrary path support for checks' and overview stats

Pick note: This is a missing bit from the first pick.

Conflicts:
	pootle/apps/pootle_store/views.py
	pootle/apps/pootle_translationproject/urls.py
	pootle/apps/pootle_translationproject/views.py
	pootle/static/js/stats.js
	pootle/templates/editor/_scripts.html
	pootle/templates/translation_projects/overview.html
Followup: Retrieve this from settings

We already picked the commit that did this change, so no idea why it is gone.
New overview page for languages

Pick notes: Had to adjust the changes because we already picked later changes
    and other changes were not necessary.

Conflicts:
	pootle/apps/pootle_language/models.py
	pootle/apps/pootle_language/views.py
	pootle/apps/pootle_misc/browser.py
Partial pick: Clarify the difference between context and resource objects

Pick notes: This is picking the missing bit that we left behind in the first
    picking.

Conflicts:
	docs/developers/glossary.rst
	pootle/apps/pootle_store/views.py
New overview page for projects

Pick notes: Had to adjust the changes because our code was different. In this
    commit we lose tags in project listing.

Conflicts:
	pootle/apps/pootle_misc/browser.py
	pootle/apps/pootle_project/models.py
	pootle/apps/pootle_project/views.py
Partial pick: Simplified item generation

Pick notes: The rest of the changes in the original commit were already
    picked in the past.

Conflicts:
	pootle/apps/pootle_misc/browser.py
Restore project listing page without any bells & whistles

Pick notes: Had to do some adjustments because of code divergence.

Conflicts:
	pootle/apps/pootle_misc/browser.py
	pootle/apps/pootle_project/views.py
Redirect to user preferred language page from the home page

If there are no matching languages, the project listing page is displayed.

(The templates haven't been removed since the home page will be reworked
sooner than later)

Pick notes: Just solved the conflicts raised because of code divergence. Now
    the code is exactly the same.

Conflicts:
	pootle/apps/pootle_app/views/index/index.py
Removed unused stuff
Cleanup: removed unused table fields

Pick note: Minor conflicts because of the priority column for goals we have.

Conflicts:
	pootle/templates/browser/_table.html
Partial pick: Cleanup: removed a bunch of dead code

Pick notes: Most of the changes were already performed. get_translate_actions
    is kept to allow displaying the translate action for the next goal.
    This will eventually be moved to the place where the other translate
    actions are created.

Conflicts:
	pootle/apps/pootle_language/views.py
	pootle/apps/pootle_misc/stats.py
	pootle/apps/pootle_misc/util.py
	pootle/apps/pootle_project/views.py
Cleanup: removed obsolete templates
Use `name` property
Cleanup: organized model attributes and properties

Now following the styleguide conventions.

Pick notes: Most of the changes were not necessary.

Conflicts:
	pootle/apps/pootle_app/models/directory.py
	pootle/apps/pootle_language/models.py
	pootle/apps/pootle_project/models.py
	pootle/apps/pootle_store/models.py
	pootle/apps/pootle_translationproject/models.py
Add INFO level to PootleCommand logging and count command running time

Pick notes: Just fixed conflicts because we use the right import order and
    respect 80 chars, and the original commit doesn't.

Conflicts:
	pootle/apps/pootle_app/management/commands/__init__.py
Hide failing checks header if there's nothing to be shown

Pick notes: Just fixed minor conflict because we moved the JavaScript code
    to a separate function.

Conflicts:
	pootle/static/js/stats.js
Cleanup: removed unused imports

Pick notes: Just minor conflicts.

Conflicts:
	pootle/apps/pootle_language/models.py
	pootle/apps/pootle_project/models.py
	pootle/apps/pootle_store/models.py