File fix-pthreads-missing.patch of Package cpp-netlib

diff -Nur cpp-netlib-0.12.0-final/libs/network/src/CMakeLists.txt new/libs/network/src/CMakeLists.txt
--- cpp-netlib-0.12.0-final/libs/network/src/CMakeLists.txt	2016-03-30 13:38:49.000000000 +0200
+++ new/libs/network/src/CMakeLists.txt	2016-04-08 00:44:58.373851583 +0200
@@ -42,6 +42,7 @@
     PROPERTIES VERSION ${CPPNETLIB_VERSION_STRING}
     SOVERSION ${CPPNETLIB_VERSION_MAJOR}
     PUBLIC_HEADER "${CPP-NETLIB_HEADERS}")
+target_link_libraries(cppnetlib-client-connections ${CMAKE_THREAD_LIBS_INIT})
 if (OPENSSL_FOUND)
     target_link_libraries(cppnetlib-client-connections ${OPENSSL_LIBRARIES})
 endif ()