crackxls2003 - Initial support for Microsoft Word

I've added initial support for scanning Microsoft Word files to the crackxls2003 program.

It is on the "msword" branch of the git repository, which is at https://github.com/GavinSmith0123/crackxls2003/tree/msword.

As with Excel files, it will only work for the RC4 method of decryption, which was used in Office XP and some earlier versions.

There is no support yet for decrypting Word documents, only scanning for their encryption keys. I haven't tried it, but it is likely that the trial version of "guaword" would be able to decrypt a file given the encryption key, as this was true for Excel files for "guaexcel", another program from the same developer.

Adding decryption support may not be that difficult, and I may manage it in the next week or so.