CI: Point to newer brew python

Makes it so that the scripting cmake variable ENABLE_SCRIPTING is a user
variable rather than a global internal cmake variable, and defers the
internal global cmake variable to SCRIPTING_ENABLED instead.

Fixing a reference to Rachni theme folder, some minor tweaks and
reverting volume meter foreground colors to original brightness.

Closes jp9000/obs-studio#1169

CI: Install swig and luajit for osx travis

Prevents Python from automatically trying to load from PATH on startup
on windows.  The user should set their Python 3 path themselves.

Prevents the user when detect-amf piped program crashes due to driver
crash.

UI: fix Multiview labels readability

This reverts commit 5cf11d67.

CI: Update CEF version on travis for osx

cmake: Search for Python 3.4

Fixes an issue where Python libraries aren't found on Ubuntu 14.04
because CMake 2.8 only searches up to Python 3.3.

Prevents simple output mode from getting stuck on an encoder that may
not be available suddenly for whatever reason (system device changes,
driver issues, etc).  If the encoder is no longer available, falls back
to x264 to ensure that the user can continue to use the program.

Showing the full directory path is sort of unnecessary and makes the
list look pretty unsightly.

UI: Add Command Line Arguments to log

Adjusts the enc-amf submodule remote to the jp9000 fork, which tests AMF
support in a separate process before attempting to initialize AMF
in-process.  Reduces the possibility of driver crashes caused by AMF
initialization.

enc-amf: Version 2.3.1

The reason this code is being reverted/removed is because this code is a
risk to startup stability.  This check will be added again in the
future, however this code needs to be executed from a secondary piped
process instead of directly in the process to reduce risk of
driver/hardware issues impacting program startup.  The same needs to be
accomplished for the AMF plugin as well.

linux-pulseaudio: Surround speaker map

Fix the image files not being freed, and remove the unused source
definition function 'update', which was additionally calling
image_source_load with the wrong number of parameters.

Adds a python example script which updates a text source to the text
retrieved from a specific URL that refreshes every specified interval.

Closes jp9000/obs-studio#1159

The decay rate of the audio meters can now be selected in the audio
settings.  The values are:

- "Fast"   (OBS default, 40 dB / 1.7s)
- "Medium" (Type I PPM,  20 dB / 1.7s)
- "Slow"   (Type II PPM, 24 dB / 2.8s)

Closes jp9000/obs-studio#1143