Reorganized layout of the source

Moving to a flatter structure with one target per directory, worked on
separating out where headers are created/installed from and consumers of
those headers.

Change-Id: I4db52813ed47e56305910b1aad386f064131cd54
Add ZeroMq include directory

Need to add the include directory so includes will be found if
we are not using system ZeroMq.

Change-Id: Ib795b7cf8e16f249590624d1252e8401a33cbfbe
BUILD_TESTING => ENABLE_TESTING

Change-Id: I82fe01c52ae2c0293367a037e1af8e3c34d7a05b
molequeue_static needs to be linked against ${QT_LIBRARIES}

molequeue_static needs to be linked against ${QT_LIBRARIES}.
Without this CMake can't correctly determine the link line and
we get strange link issues.

Change-Id: Ia200c79b58196cef6e8ae9b9e5f9cc16634d5f86
Merge topic 'molequeue-reorganization' into master

ca72dfa8 molequeue_static needs to be linked against ${QT_LIBRARIES}
23d624f0 BUILD_TESTING => ENABLE_TESTING
e50bb619 Add ZeroMq include directory
05d154a2 Reorganized layout of the source