units.py: convert(): Added support for unit conversions. Added initial unit conversion for % -> unitless. str2quantity(): Fixed regexp to match % as units. Set Quantity.__repr__ to quantity2str.

units.py: convert(): Put "units None" test after "quantity.units units" test because a destination of no units might require a conversion for some input units (e.g. % -> unitless requires a division by 100)

inputs/SALVIAS*/maps/VegX.organisms.csv: Habit: Ignore invalid values instead of generating a SyntaxException

xml_dom.py: minidom modifications: Escape as many text strings as we use directly. This still leaves the tagName used by xml.dom.minidom.Element.writexml: It uses 'writer.write(indent+"<" + self.tagName)' and doesn't escape the tagName.

xml_func.py: Made everything Unicode-safe by using strings.ustr instead of str

schemas/tree_cross-links.sql: Added comment for how to get the namedplace trigger from the provided plantname trigger

vegbien.sql: Fixed bug in tree cross-link algorithm where recursion to descendants' ancestors did not use new to refer to the current node's plantname_id

vegbien.sql: Fixed bug in tree cross-link algorithm to also insert ancestors for top-level nodes, because they now need an ancestor entry for themselves

Added separate SQL file for tree cross-links code. A link to this can be e-mailed to people to review.

vegbien.sql: Modified tree cross-link algorithm to add an "ancestor" for this node. This is useful for queries, because you don't have to separately test if the leaf node is the one you're looking for, in addition to that leaf node's ancestors.