The user can add an arbitrary number of highly configurable
shell commands through the setting panel. The commands can
be saved as user preferences, inside the .fl file, or exported
to an external file. Shell scripts can be limited to individual
platforms, can have shortcut keys, etc. .
* documentation will follow
* support to call `fltk-config` will follow
* interactive layout alignment rewritten
* interface for new alignment rules
* new alignment dialog box
* user defined layout rules added
* layout rules can be stored in projects, settings, and external files
* Valgrind verification
