Remove isnan() and isinf() templates from QGC.h for Windows builds, this
generates errors (already defined in math.h).

Add msvc2013 to build types

First QT5 PR, all core functionality works

Add debug output for when voice initialization fails on Windows

Removed or annotated existing commented-out code

Clean up logic for saying emergency text.

Previous code didn't properly check for if speech was enabled.

Mavlink submodule

Some functionality was lost, will need to be fixed in a later commit.

Fix invalid images in mavlink video transmission.

Therefore Mouse3DInput has been changed to now inherit from that base class and implement the necessary interface.

To include OpenGL primitives, we include the QtOpenGL header instead, which has all the platform-specific includes taken care of for us.

Added an exists() call beforehand.

Now all prerequisite packages should be listed for Arch, Fedora, and Ubuntu.

Updated some URLs, docs, and packages. Ubuntu and Arch instructions have not been verified on a live install, but the names come from their online package listings, so they should be correct.