Patch is a simple program that provides a way to alter a file, using a
pre-written ASCII text file that describes how the patch is to be done.  To
describe the patch to the program, you use several lines of data that start
with special characters:

;=comment.  All data on the line will be ignored.
O=Offset to begin patching data at
T=Text to insert into file
D=Double word of data to insert
W=Word of data to insert
B=Byte of data to insert

All data and offsets must be specified in a decimal format.  This may be fixed
in a later version.  For now, it is just an inconvience.  They can be negetive
though.  :)

Please note that the above control characters MUST be the first character on
the line.  Sorry, comments cannot be placed on the same line as data, yet.

Here's an example of what I mean:

;This is a comment

;Offset of 1st thing in hexen.exe
O=785604

;Put a 4 byte integer into the file and increment file pointer by 4 bytes
D-1

;Put a 2 byte integer into the file and increment file pointer by 2 bytes
W10

;Put in some text of the exact length of the line (not including the T at the
;beginning of the line.  Trailing spaces are stripped off.
THello
;Note: You have to set terminators/length bytes of text data yourself.


Usage:
patch patchfile.ext

Right now, it just patches the file named hh.exe in the current directory.
I'll probably make it so you can specify the file on the command line in a
later version.  If you're using this with Hexen, just copy hexen.exe to
hh.exe.  Simple enough, right?
