new option menu for solvers (much simpler than in gear menu); needs to be enhanced with other actions

only use preset file name the first time a file chooser is used; all later times use the last-visited directory

than native here (for a large number of strings))

No commit message

don't create element cache by default (it's quite slow on really large meshes); we'll create it if needed on demand

slow, disabled by default)

control the explicit scheme via the python script (onelab integration)