there and back again
Point & Size now support * and / operators

- also tightened up operand type coercion
- no longer raises an exception when testing equality against non-tuple
types
moved XML parsing into Text.append

- the node lookup table now gets tended by the frame-setter
moved node-tracking back to the parent Text
added regex- and tag-based queries to Text

- the .find method takes a regex pattern and returns the layout
information for all matching portions of the displayed text
- the .select method works the same way but takes a tag name (making it
useful in conjunction with xml-based Text objects)
- both methods return a list of TextMatch objects with attributes
describing the match in terms of the original string
- the match object’s .layout property is a list of one or more
LineFragments describing the glyph geometry in minute detail