To include library for RADIUS authentication in the docker image the
build needs to activate the maven profile "lgpl-extentions" and copy
the library into the image.
The docker start script needs to pass through settings and link the
library to GUACAMOLE_HOME.
There's no need to clean up the local Maven repository after the
build, since only the artifacts we want are copied to the runtime
image. For reasons not investigated, attempting to remove the
local repository directory fails because the directory is in use
after the build.
