Add section about contacting mods in welcome message

Author: technetos

src/text.rs

@@ -1,6 +1,8 @@
 pub(crate) const WELCOME_BILLBOARD: &'static str = "By participating in this community, you agree to follow the Rust Code of Conduct, as linked below. Please click the :white_check_mark: below to acknowledge and gain access to the channels.
 
-  https://www.rust-lang.org/policies/code-of-conduct  ";
+  https://www.rust-lang.org/policies/code-of-conduct
+
+If you see someone behaving inappropriately, or otherwise against the Code of Conduct, please contact the mods using `@mods` or by DM'ing a mod from the sidebar.  ";
 
 pub(crate) fn ban_message(reason: &str, hours: u64) -> String {
     format!("You have been banned from The Rust Programming Language discord server for {}. The ban will expire in {} hours. If you feel this action was taken unfairly, you can reach the Rust moderation team at [email protected]", reason, hours)