New real terminal emulator, replacing the old plugin.
The emulator is basically a vt52 terminal (enriched with
some ANSI-sequences, as ash, vi and mksh don't behave well
on a vt52 term).
So far working: ash, mksh, bash, nano, vi, busybox, watch...
The input supports: tab-completion; cursor movement;
backspace; start of line, end of line (long press);
page up, page down (long press).
User scripts may be placed in the koterm.koplugin/scripts/
folder, aliases can be put in the file aliases and startup
command in the file profile.user in that folder.
