This does two main things:
1) The importer now imports as numbers, not parsed strings. This allows
is to format values on output instead of input, which is what was
happening in most places.
2) Add a Helper::parseCurrencyString method and port everything to use
this. This checks to see if the value is numeric or empty, and returns
the appropriate value in all cases. Should fix all known occurances of
number_format expections.
* Update tableexport.js to the new version.
* Give the export file in each table a useful name.
The name takes the form of tabletype-export-YYYY-MM-DD.extension.