Fixed #1190: Wrong sorting of motion identifier

- Added natural sorting JS plugin for motion DataTables (column identifier).
- Added the new requirements python package 'natsort' for natural sorting of motions in PDF.
Merge pull request #1192 from emanuelschuetze/naturalsort

Fixed #1190: Wrong sorting of motion identifier
Fixed #1138: Wrong file for projectors logo
Merge pull request #1207 from emanuelschuetze/fix-1138

Fixed #1138: Wrong file for projectors logo
Reinserted icon and link for preview of agenda slide. Fixed #1199.
Merge pull request #1211 from normanjaeckel/PreviewAgenda

Reinserted icon and link for preview of agenda slide. Fixed #1199.
fix for python2.6 and pip 1.5
Merge pull request #1218 from ostcar/argparse_fix

Fix for Python 2.6 and Pip 1.5 (use of argparse 1.2.1)
Merge remote-tracking branch 'openslides/stable/1.5.x'

Conflicts:
	extras/win32-portable/create_portable.txt
	extras/win32-portable/prepare_portable.py
	openslides/motion/templates/motion/motion_list.html
	openslides/projector/templates/projector.html
	requirements_production.txt
changed dependency to python 2.6.9
Merge pull request #1219 from ostcar/python2.6.9

Changed dependency to python 2.6.9
Regrouped config collections and pages. Fixed #1201.
Merge pull request #1210 from normanjaeckel/RegroupConfig

Regrouped config collections and pages. Fixed #1201.
Added extra permission check to speaker widget, fixed #1191 only for 1.5.x branch
Merge pull request #1216 from normanjaeckel/SpeakerWidgetPermission

Added extra permission check to speaker widget, fixed #1191 only for 1.5...
Fixed flake8 errors.
Merge pull request #1225 from normanjaeckel/Flake8Errors

Fixed flake8 errors.
Fixed #551: Used unicode font for circle in ballot pdf. Removed pillow.

That fixed also #1140 (Server error when trying to view ballot paper pdf)
Merge pull request #1215 from emanuelschuetze/fix-551

Removed pillow. Used unicode circle font. (Fixed #551 and #1140)
fix user status view (activate, deactivate user without js)