[Asterisk-doc] a few lines

[Randy Resnick]

Randy Resnick wrote:

Errr,

  ***ADD***: If a mailbox to be checked is not in the default context in
  voicemail.conf you must explicity provide the context as in

  		mailbox=1000,2000@smokers,2001@drinkers

where mailbox 1000 is in defaul, 2000 is in a voicemail.conf context
called smokers and 2001 is in the context called drinkers.

small typos/errors

from Hardware installation where some errors were introduced:

  If you are dedicating the computer to Asterisk, free up as many IRQs as
possible by disabling USB, serial and parallel port support in the BIOS.
Otherwise, you still will want to free as many as possible.

from X100P paragraph

The only difference between an X100P and X101P is a slight difference in
chips, but makes no difference to it's operation.

Suggest you change this to

The only difference between the X100P and X101P is a slight difference 
in their respective chips, but this has no effect on their use with 
asterisk.

Note that using It's to mean something belonging to or related to 'it' 
has to be one the most common grammatical error in English writing. 
Someone might want to grep the whole book for "[Ii]t's" and make sure 
all of these are contractions of "it is."

The other usage "ain't correct" :)