Merge pull request #6 from sschum/master

Some little changes
Merge pull request #7 from sschum/osng-477

Osng 477
add integration tests for paging and fix some bugs
fix message name for german internationalisation
reorder the user specific controllers into a new subpackage
add edit button to go to the user edit-mode
remove unnecessary Actions-Button in user view
Merge branch 'osng-471' of github.com:sschum/addon-administration into osng-476
add link for back button in edit user view
make filter button primary
replace EMPTY_MAP constant with method-call
code styling
let throw custom exception if the user was not found
rename enum-constants to uppercase
user URIBuilder instead of using string concatenation
use URIBuilder instead of using string concatenation
little restructure for paging builder
* remove unused methods
* remove unnecessary null checks
Merge pull request #8 from sschum/osng-471

Osng 471
merge with upstream master