upload cleanup + tests

remove cruft, reformat some for readability, more tests
uploader integration tests running and passing

- cleanup old stuff
- add test_uploader user for better layer cleanup
- update README for running tests
- reduce number of logins and use reverse for url
- fix permissions
- use reverse for login url
- make view logger use error level to prevent msg getting
  swallowed
continued upload fixes

- save time related transforms
- implement set_time_info with tests (requires gsconfig update)
- use set_time_info in upload instead of non-existing function
- fix form to correspond to fields used in template, add clean and tests
- integration test fixes + cleanup
- don't use bigdate transform for geogit

other:
- provide default port for geoserver datastore if missing and check if
  enabled
- remove superfluous check for layer in upload
- pep8
uploader client-side fixes

- fix for 'Mismatched anonymous define' error in time page by relocating
  script load order
- refactor logStatus and logError to common module, support more options
  and fix various broken use of `self.markError`
- refactor doUpload to time module
- minor style/html cleanup on time page
- fix incorrect form field name on time page
- cleanup various dangling commas
- don't probe geogit stores unless enabled
Added requested languages from transifex
Updated translations
Added messages for new languages
Updated .mo
Updated .po from transifex
Updated locale with dummy data so they are picked up by tx push
Used google's workbench to translate 30% of arabic
Manual fixes to arabic django.po
Updated arabic
Updated changelog for version 2.4a22
comment the amharic language
limit the model translation language to english by default. Add the settings for translated languages.
add missing...space
clear map thumbs logic
Merge pull request #1765 from simod/map-cleanup

clear map thumbs logic
changed temporal extent fields to DateTime