Update command summary page with new CV BYTE format

[peteGSX]

The command summary page needs to be updated to deprecate the old format, and provide the new as advised by @Ash-4 and @mstevetodd :

Old format: Write CV BYTE Format is: RETURNS: <r CALLBACKNUM|CALLBACKSUB|CV Value>

New format: Write CV BYTE Format is: RETURNS:

https://dcc-ex.com/reference/software/command-reference.html?highlight=write#write-cv-byte-to-engine-decoder-on-programming-track

[peteGSX]

Missed escaping:

Old format: Write CV BYTE Format is: \ RETURNS: \<r CALLBACKNUM|CALLBACKSUB|CV Value>

New format: Write CV BYTE Format is: \\ RETURNS: \

https://dcc-ex.com/reference/software/command-reference.html?highlight=write#write-cv-byte-to-engine-decoder-on-programming-track