Add --run command line option to Howl

Allows loading and executing a specified file from the command line
in the Howl environment.
Use table.pack instead of select '#'
ljglibs: Add cairo, pango, GtkDrawingArea, etc.

Mostly lots of stuff needed for custom drawing.
Add initial WIP version of Aullar, a new editing engine

Which will supersede Scintilla in the long term. Currently we're at very
early stages, limited to plain displaying and simple editing of text
without scrolling.
Add aullar-test script

Allows for testing out the new editing component. Supports specifying
a file to open from the command line.
Add aullar specs to run-all-specs