process.js tries to parse all files in the data folders, including the cache files

[UncleGus]

This is only an issue when pointing onetech at local data files, since these cache files are ignored by git, so won't be included when downloading the data.

Most data folders get cached by the client, server and editor into files called cache.fcz. These should be disregarded when processing data files.

[ryanb]

I'll make it filter out only *.txt and *.tga files, whichever it needs.