Introduce function for particle bounding rectangle instead of two separate functions for width and height

Disable ManhattanStyle, that fixes background colors of some widgets under (at least) Plasma desktop manager.

* Make names more uniform: FormFactorRipple1* where *=Box,Gauss,Lorentz
* Implementation through inheritance from ProfileRipple1
* Form factor in elongation direction x computed in namespace ripples

In passing, eliminate a few other warnings too.

adapt GUI to change of FormFactorDot argument