Patch Scintilla to fix pasting from external Win32 apps; src/scintilla.patch
Move the command entry into a split pane on GTK.
In the previous implementation without a split pane, the command entry could not
shrink in size.
Grow and shrink views by an integral, not arbitrary, value.
Parameterize lexer and height for `ui.command_entry.enter_mode()`.
Also enable more accurate Lua command completion.