Replace travis with github actions (#9641)

* Move outside of travis to Github actions

This will permit to have better integrated CI workflow than the previous
travis one.

util/ci/build.sh

@@ -0,0 +1,8 @@
+#! /bin/bash -eu
+
+mkdir cmakebuild
+cd cmakebuild
+cmake -DCMAKE_BUILD_TYPE=Debug \
+	-DRUN_IN_PLACE=TRUE -DENABLE_GETTEXT=TRUE \
+	-DBUILD_SERVER=TRUE ${CMAKE_FLAGS} ..
+make -j2