Add documentation for NumberParse filter

Related to zendframework/zf2/#4493 and zendframework/zf2#4510
Update service manager config key for the identity plugin()

'alias' key should be 'aliases'
Merge branch 'hotfix/#875'

Close #875
Merge branch 'feature/add-documentation-for-number-parse-filter' of https://github.com/localheinz/zf2-documentation into hotfix-#884
Merge branch 'patch-1' of https://github.com/gsteel/zf2-documentation into hotfix/#885
Merge branch 'hotfix/#885' into develop

Close #855