Separate global settings for each Android user

Closes #1563
Security for multiple users

Refs #1563
Security for multiple users

Refs #1563
Merge branch 'master' of github.com:M66B/XPrivacy
Use original uid

Refs #1563
Use original uid

Refs #1561
Refs #1563
Merge branch 'master' of github.com:M66B/XPrivacy
Fix security for usage list

Refs #1563
Secondary users can only see own use data

Refs #1563
Layout improvement for multiple users

Refs #1563
Display usage data for last three hours
Updated changelog
Updated FAQ
Updated FAQ
Updated description
Updated features
Some performance optimizations