Support for TOH/TOT and some fixes

Hi Wisp,

I have once again spent some time with the Near Infinity sources. As a result, TOH/TOT support and the missing Pocket Plane location structure in GAM files have been added.

In the course of adding TOT support I had to develop the new class 'infinity.datatype.TextEdit' which provides a multi-line string editor. Maybe it is useful for other file formats as well.

Cheers,
Argent77