Compile fix for non-standard Qt5 install.

When Qt5 5.2.1 is compiled from source, configured with
-developer-build, and used without being installed;
then compiling interface results in the following compile error:

libraries/shared/src/RegisteredMetaTypes.h:17:34: fatal error: QtScript/QScriptEngine: No such file or directory

This commit fixes this by explicitely adding the include
directory for QtScript/QScriptEngine to libraries/shared/CMakeLists.txt

Likewise we get the compile error:

In file included from /opt/highfidelity/hifi/hifi/animation-server/../libraries/voxels/src/VoxelEditPacketSender.h:18:0,
                 from /opt/highfidelity/hifi/hifi/animation-server/src/AnimationServer.cpp:26:
 /opt/highfidelity/hifi/hifi/animation-server/../libraries/voxels/src/VoxelDetail.h:15:34:
 fatal error: QtScript/QScriptEngine: No such file or directory

which is fixed by added the include directory for QtScript/QScriptEngine
to animation-server/CMakeLists.txt

Finally, compile errors like

In file included from /opt/highfidelity/hifi/hifi/libraries/audio/src/AudioInjectorOptions.h:20:0,
                 from /opt/highfidelity/hifi/hifi/libraries/audio/src/AudioInjector.h:21,
                 from /opt/highfidelity/hifi/hifi/libraries/audio/src/AudioInjector.cpp:22:
/opt/highfidelity/hifi/hifi/assignment-client/../libraries/shared/src/RegisteredMetaTypes.h:17:34: fatal error: QtScript/QScriptEngine: No such file or directory

that requires to do the same in libraries/audio/CMakeLists.txt
Fix a (possible) crash in QObject::disconnect

This is https://worklist.net/19827