Build: Update libosg to latest version to remove link error

Add dylibs for libosg; built from OpenSceneGraph-3.2.1 using:
cmake -G Ninja -DOSG_USE_QT=OFF -DBUILD_OSG_APPLICATIONS=OFF && ninja

ffmpeg plugin failed to compile (probably version mismatch), but that's no big deal;
everything else built and we don't need that plugin.  Indeed we probably don't need most
of these plugins, but might as well copy them I guess since disk is cheap these days.
Libs: opmapcontrol - Fix error while compiling moc-generated file; GeoCoderStatusCode is not in internals namespace
Libs: osg - Change conditional include to fix std:isnan vs isnan warning for diydrones/apm_planner#40

This is actually an odd bug.  The compiler seems to sometimes double-up on the std:: prefix and think it's looking for std::std::isnan or something.  But sometimes not.  Anyway, this fixes it the simple way.
Map3D: Fix getAltitude() to getAltitudeAMSL() in Google Earth module
Qt5: Big commit switches to building for Qt5

I've only built using Qt 5.3.1 for OSX; I *think* everything should work OK on Linux and Windows, but not tested.
There are a couple notes:

* Update libs/qwt to version 6.1.0 since the old version didn't Qt5 nicely.
* Side effect of above is that I'm not sure I correctly dealt with PaintOutsidePaintEvent going away properly in src/ui/linechart/LinechartPlot.cc
* Also not sure that the changes in src/ui/QGCDataPlot2D.cc are correct at all in print() and exportPDF()
OSX: Fix speech generation code to not badly mis-hack a Pascal string and use newer APIs

The OSX speech generation code was passing a bad Pascal string to an ancient deprecated API
Now we pass the string correctly as a C string and call the correct modern API

diydrones/apm_planner#40
Build: Turn "warnings are errors" on for Mac and Linux

diydrones/apm_planner#40
Comms: Fix to undo tautological code

diydrones/apm_planner#40
Libs: opmapcontrol Remove unused variable declaration

diydrones/apm_planner#40
configuration: Remove deprecation warning on OpenSSL for OSX

diydrones/apm_planner#40
configuration: QByteArray.size() is a signed int, not unsigned.  Just in case your file has negative size, I guess.  Otherwise how will physicists store anti-files?

diydrones/apm_planner#40
UI Framework: Handle unhandled cases in switch() statements

diydrones/apm_planner#40
Libs: alglib - remove unused definitions of variables and functions for diydrones/apm_planner#40
Libs: alglib - remove spurious "const" specifier on returned bool value for diydrones/apm_planner#40
Libs: alglib - Mark unused parameters as unused for diydrones/apm_planner#40
Libs: Eigen - flag two unused parameters as unused for diydrones/apm_planner#40
Libs: libosg - unhide overloaded virtuals to remove warning for diydrones/apm_planner#40
Warnings: remove spurious parentheses in if() expression

diydrones/apm_planner#40
Warnings: QDomNodeList::length() returns an int not a uint

diydrones/apm_planner#40
Warnings: fix out-of-order member initialization in constructors

diydrones/apm_planner#40