added opencv imgproc to dependencies

```
$ ./qtox
./qtox: error while loading shared libraries: libopencv_imgproc.so.2.4: cannot open shared object file: No such file or directory
```
Starting client activates existing instance if such exists
Added -P <profile> parameter which makes qTox start (and not activate any existing instances) and load specified profile
-P value name also translated
No border for message area (as in mockup)
Added Spanish translation