[CMake] replace main LIBRARY_NAME by PROJECT_NAME

Just to avoid the confusion of having 2 things with the same name
without a clear reason

CMakeLists.txt

@@ -65,8 +65,6 @@ SEARCH_FOR_PTHREAD()
 ####################################
 ### Main Library
 ####################################
-SET(LIBRARY_NAME ${PROJECT_NAME})
-
 # Verbosity level
 IF (NOT (\"${CMAKE_VERBOSITY_LEVEL}\" STREQUAL \"\"))
   ADD_DEFINITIONS(-DVP_DEBUG_MODE=${CMAKE_VERBOSITY_LEVEL} -DVP_DEBUG)
@@ -153,7 +151,7 @@ SET(${PROJECT_NAME}_HEADERS
   include/dynamic-graph/logger.h
 )
 
-ADD_LIBRARY(${LIBRARY_NAME}
+ADD_LIBRARY(${PROJECT_NAME}
   SHARED ${${PROJECT_NAME}_SOURCES} ${${PROJECT_NAME}_HEADERS})
 
 SET(PUBLIC_HEADER ${${PROJECT_NAME}_HEADERS})
@@ -177,13 +175,13 @@ target_include_directories(${PROJECT_NAME}
    $<INSTALL_INTERFACE:include>
    )
 
-SET_TARGET_PROPERTIES(${LIBRARY_NAME} PROPERTIES SOVERSION ${PROJECT_VERSION})
+ SET_TARGET_PROPERTIES(${PROJECT_NAME} PROPERTIES SOVERSION ${PROJECT_VERSION})
 
 IF (UNIX)
-  TARGET_LINK_LIBRARIES(${LIBRARY_NAME} ${CMAKE_DL_LIBS} pthread)
+  TARGET_LINK_LIBRARIES(${PROJECT_NAME} ${CMAKE_DL_LIBS} pthread)
 ENDIF (UNIX)
 
-TARGET_LINK_LIBRARIES(${LIBRARY_NAME} ${Boost_LIBRARIES})
+TARGET_LINK_LIBRARIES(${PROJECT_NAME} ${Boost_LIBRARIES})
 
 ####################################
 ### Plugins