TONS of translation-related changes

Mostly subtle changes to help automate the master translation file
generation process.  In most cases, this consists of removing redundant
text, using more concise wording, and breaking complex text merging
operations into smaller, more easily parseable chunks.
New automatically generated master translation file

I wrote a program to generate this from the source code.  It works very
well, but there are a lot of custom PhotoDemon-specific bits.  (I say
this in case others ever try to adopt it for their own purposes - they
will need to do some tweaking of their own.)
Hand-edited master translation file.

Should be 100% accurate and correct.  Going forward, all text changes
will be reflected in this file.