make force_lock_settings default to true for [scenario]

In most cases the campaigns designer don't want the use to be able to
overwrite scenario properites like "turn limit" or "use fog".

It is easiert to do this here in the code that loads the config than in
the code that reads that value becasue there are multiple codes that
read it and it's not clear that all of then know whether teh scenario
was a [multiplayer] or a [scenario].

Partly implements http://gna.org/bugs/?23037 which suggests to remove
the ability to overwite those settings in capaigns completely.
Move apple_notifications.mm somewhere easy to find for scons.
Require __APPLE__ to build apple_notification.mm in case another compiler runs into it.
File assumes the presence of many OS X specific headers and definitions.
Speculative change to support homebrew.
I don't actually have it, so hopefully it works.
Conditionally added because I don't know if all compilers even hope to compile
Objective-C++ and I don't want to incidentally break other builds.
Fix typo which put comment partially on the wrong line.
DiD S12: used [switch] instead of multiple [if]s where applicable
DiD S1: used a victory event instead of including the whole cutscene code twice
DiD S2: create Volk before start, thereby removing a noticeable delay before the initial dialog
DiD S3: used [filter_condition] to reduce excessive [if] indent
travis: fix obscure bug related to apt-get ugprade

http://serverfault.com/questions/563073/postgresql-9-3-installation-fails
travis: fixup previous commit
travis: fixup previous commit
travis: remove apt-get upgrade
DiD S5: made use of filter_condition
DiD S6: simplified some code
Made more use of [filter_condition]
Did S9.3: made more use of [filter_condition]
DiD S10: code cleanup, and made use of [filter_condition]
DiD S11: code cleanup, and yes, [filter_condition]
Fixed some backwards logic in CREATE_ADVISOR