[i/214] resolving problems with search at activitypage

Old commit messages:

[i/214] adding redirection a proper direction

[i/214] properly escaping $username string usages

[i/214] adding filter for empty input

[i/214] replacing "or" with "||"
Merge pull request #214 from Senky/i/214

If there is no sutable result for user search, user is redirected to activitypage