refactor and integrate with aliBuild/alienv

* accept ZEROMQ_ROOT as env or cmake variable to hint at install
    location (used by aliBuild/alienv)
  * added more docs
  * fixed mismatch between module name ZeroMQ and prefix of
    generated variables ZMQ -> ZeroMQ is now the preferred prefix
    (old variables are still available and marked deprecated)
  * the aliBuild zeromq recipe does not install zmq.hpp header,
    so the module searches now for the zmq.h header
    (which is anyways the only one we use)
  * some cosmetic changes
  * add option ZeroMQ_NO_DEPRECATION to suppress deprecation warning

examples/MQ/1-sampler-sink/CMakeLists.txt

@@ -22,7 +22,7 @@ Set(INCLUDE_DIRECTORIES
 
 Set(SYSTEM_INCLUDE_DIRECTORIES
   ${Boost_INCLUDE_DIR}
-  ${ZMQ_INCLUDE_DIR}
+  ${ZeroMQ_INCLUDE_DIR}
 )
 
 Include_Directories(${INCLUDE_DIRECTORIES})

examples/MQ/2-sampler-processor-sink/CMakeLists.txt

@@ -22,7 +22,7 @@ Set(INCLUDE_DIRECTORIES
 
 Set(SYSTEM_INCLUDE_DIRECTORIES
   ${Boost_INCLUDE_DIR}
-  ${ZMQ_INCLUDE_DIR}
+  ${ZeroMQ_INCLUDE_DIR}
 )
 
 Include_Directories(${INCLUDE_DIRECTORIES})

examples/MQ/3-dds/CMakeLists.txt

@@ -25,7 +25,7 @@ Set(INCLUDE_DIRECTORIES
 Set(SYSTEM_INCLUDE_DIRECTORIES
   ${SYSTEM_INCLUDE_DIRECTORIES}
   ${Boost_INCLUDE_DIR}
-  ${ZMQ_INCLUDE_DIR}
+  ${ZeroMQ_INCLUDE_DIR}
 )
 
 Include_Directories(${INCLUDE_DIRECTORIES})

examples/MQ/4-copypush/CMakeLists.txt

@@ -22,7 +22,7 @@ Set(INCLUDE_DIRECTORIES
 
 Set(SYSTEM_INCLUDE_DIRECTORIES
   ${Boost_INCLUDE_DIR}
-  ${ZMQ_INCLUDE_DIR}
+  ${ZeroMQ_INCLUDE_DIR}
 )
 
 Include_Directories(${INCLUDE_DIRECTORIES})

examples/MQ/5-req-rep/CMakeLists.txt

@@ -22,7 +22,7 @@ Set(INCLUDE_DIRECTORIES
 
 Set(SYSTEM_INCLUDE_DIRECTORIES
   ${Boost_INCLUDE_DIR}
-  ${ZMQ_INCLUDE_DIR}
+  ${ZeroMQ_INCLUDE_DIR}
 )
 
 Include_Directories(${INCLUDE_DIRECTORIES})

examples/MQ/6-multiple-channels/CMakeLists.txt

@@ -22,7 +22,7 @@ Set(INCLUDE_DIRECTORIES
 
 Set(SYSTEM_INCLUDE_DIRECTORIES
   ${Boost_INCLUDE_DIR}
-  ${ZMQ_INCLUDE_DIR}
+  ${ZeroMQ_INCLUDE_DIR}
 )
 
 Include_Directories(${INCLUDE_DIRECTORIES})

examples/MQ/8-multipart/CMakeLists.txt

@@ -22,7 +22,7 @@ Set(INCLUDE_DIRECTORIES
 
 Set(SYSTEM_INCLUDE_DIRECTORIES
   ${Boost_INCLUDE_DIR}
-  ${ZMQ_INCLUDE_DIR}
+  ${ZeroMQ_INCLUDE_DIR}
 )
 
 Include_Directories(${INCLUDE_DIRECTORIES})