Move some content into the main Bro docs

Moved some content regarding how to setup a Bro cluster into the
main Bro docs (in a new section "Cluster Configuration").
Merge remote-tracking branch 'origin/master' into topic/dnthayer/ticket1186
Rename the broctl option pfringdnafirstappinstance

Renamed pfringdnafirstappinstance to pfringfirstappinstance (i.e.,
removed the "dna" in the name) because the name is quite long and
this option is also used with ZC (and DNA is supposedly going away
sometime in the future).
Merge remote-tracking branch 'origin/fastpath'

* origin/fastpath:
  Rename the broctl option pfringdnafirstappinstance
Merge remote-tracking branch 'origin/topic/dnthayer/ticket1186'

* origin/topic/dnthayer/ticket1186:
  Move some content into the main Bro docs

BIT-1186 #merged
Update broctl.rst with "make doc" (no other changes)
Improve documentation of PFRINGFirstAppInstance option
Merge branch 'fastpath'
Update submodules, CHANGES, VERSION.
Remove references to the now unused BROMAGIC
Merge remote-tracking branch 'origin/fastpath'

* origin/fastpath:
  Remove references to the now unused BROMAGIC
Updating CHANGES and VERSION.
Fix for capstats with PF_RING+DNA pfdnacluster_master

When using PF_RING+DNA with pfdnacluster_master, an application doesn't
work if it tries to use the same interface name that Bro is using, so
a quick fix to get capstats working again is to give it a copy of the
interface name with the "@n" suffix removed.
Fix for capstats to display correct interface name

Show the correct interface name in capstats when using PF_RING+DNA with
pfdnacluster_master.
Merge remote-tracking branch 'origin/fastpath'

* origin/fastpath:
  Fix for capstats to display correct interface name
  Fix for capstats with PF_RING+DNA pfdnacluster_master
Updating submodule(s).

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Updating CHANGES and VERSION.
Updating submodule(s).

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Updating submodule(s).

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Updating submodule(s).

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