command-prompt: Basic line editing

Left/right arrows, Ctrl-A, Ctrl-E
Fix 4/6 behavior
Command-prompt history

Creates duplicate entries occasionally

Also disabled movies
Merge branch 'develop' into cmdprompt-lineedit
Merge branch 'develop' into cmdprompt-lineedit
Remove (broken) command history

This reverts commit cc07a373f3b48918060da2800e83d4f37eeb34a5.
Reimplement command-prompt history

Also add shift-left/right for back/forward one word
Prevent blank lines from being stored in history
Merge remote-tracking branch 'lethosor/cmdprompt-lineedit' into 0.34.11-r5