permit subdirectory for JAR_PATH

[TrogloGeek]

I configured DEFAULT_JAR_PATH as following:

DEFAULT_JAR_PATH="bin/server.jar"

It broke server_set_jar() if I don't manually create the bin folder for every server.
I modified the code as follows:

        if [[ ! -z "$jar" ]]; then
            as_user "${SERVER_USERNAME[$1]}" "ln -sf \"$jar\" \"${SERVER_JAR_PATH[$1]}\""
            echo "Server \"${SERVER_NAME[$1]}\" is now using \"$jar\"."
        fi

became

        if [[ ! -z "$jar" ]]; then
            local server_jar_dir=$(dirname "${SERVER_JAR_PATH[$1]}")
            if [ ! -d "$server_jar_dir" ]; then
                as_user "${SERVER_USERNAME[$1]}" "mkdir -p -m 0700 '$server_jar_dir'"
            fi
            as_user "${SERVER_USERNAME[$1]}" "ln -sf \"$jar\" \"${SERVER_JAR_PATH[$1]}\""
            echo "Server \"${SERVER_NAME[$1]}\" is now using \"$jar\"."
        fi

I also made a minor "improvement" (but perhaps you won't like it) to allow me issuing the msm server set jar command omitting the .jar extension :

            if [[ ! -e "$jar" ]] && [[ -e "$jar".jar ]]; then
                jar="$jar".jar
            fi

            if [[ ! -e "$jar" ]]; then
                error_exit NAME_NOT_FOUND "There is no jar named \"$3\" in jargroup \"$2\"."
            fi