mblaze.7: update man page

[larryhynes]

The changes to this file illustrate a number of changes that I would like to incorporate in the other man pages.

• We refer to maildir throughout (not Maildir) sometimes 'maildir folder' This is inline with djb's original spec

• We refer to messages, sometimes (but rarely) 'mail messages'

• We refer to 'mail address', 'mail header' This goes back all the way to RFC 524

• We refer to mbox files (not mailbox) This is in line with RFC 4155

• We're dealing with the 'mblaze message system'

• Which is composed of 'utilities' (not 'tools')

• The description of each utility will, as closely as possible, be the same as its SYNOPSIS in its own man page. (This will be a work in progress!)

There are some other changes here:

• I've removed procmail, on the grounds that it doesn't fetch mail.
• A missing comma
• Stray parentheses in mailing list details
• Use mdoc's .Po and .Pc to for parenthetic enclosure, as per @duncaen
• 'processing and interacting with' instead of 'dealing'

So this should give you a good idea of where I want to go with the other man pages, which is basically get everything in line, as much as possible, with the concepts here. I think it will be clearer in the long run, and easier to incorporate new material as time goes by.

[leahneukirchen]

In general, :+1:, but I have a few nits.

[larryhynes]

Only to be expected!