update contribution guides (more visibility to forums)

gcontini

2020-10-09 ea3f019f6061d8fd67a9b71601605a823cedf050

 test/library/CMakeLists.txt

@@ -14,7 +14,7 @@
ELSE(WIN32)
    add_executable(
       test_os_linux
       Os_Linux_test.cpp
       os_linux_test.cpp
   )

   target_link_libraries(