feature request, shift-enter to inline a newline

[Alex fxmbsw7 Ratchev]

as title says, pressing shift enter would produce a newline into all
instead of send the cmd away

this is handy when editing data around on the terminal ( i saw it well
working with copypaste )
and when multiple commands are, like they are already expanded, now
editing in the middle something somewhat of requires a newline .. but
sending one errors in sending the whole cmd away

cheers