With --thread a signle thread ID or thread URL can be entered.
If thread is a URL, it will download it.
If thread is an ID, a category must also be set.
Configuration Settings can now be changed with the -e command line argument
execution of 4grab has been moved to 4grab.py, but should also still work with download.py
* Seperated the parser from the downloader code.
* Added a progressbar class, to make it look fancier
* Created some functions to do all the work in downloader.py, cleaner now
* Changed parser.py to htmlparser.py, since it was conflicting with a built-in module