esrf changes: CMake: support to be added and installed as a sub-project:

* Configure zmq as global imported library in slsReceiverSoftware
* Install zmq, necessary if linking to slsReceiver library

slsDetectorSoftware/CMakeLists.txt

@@ -39,12 +39,6 @@ add_definitions(
     -DDACS_INT
 )
 
-add_library(zmq STATIC IMPORTED )
-
-set_target_properties(zmq PROPERTIES
-    IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/../slsReceiverSoftware/include/libzmq.a
-)
-
 add_library(slsDetectorStatic STATIC
     ${SOURCES}
     ${HEADERS}