cmake: added optimization and at the same time added the beta-NMR lib.

src/external/MusrRoot/CMakeLists.txt

@@ -30,6 +30,9 @@ set_target_properties(TMusrRunHeader
     VERSION ${MUSR_ROOT_VERSION}
 )
 
+#--- add compile options for optimization -------------------------------------
+target_compile_options(TMusrRunHeader PUBLIC -O3)
+
 #--- add library dependencies -------------------------------------------------
 target_link_libraries(TMusrRunHeader ${ROOT_LIBRARIES})