fix error message to also suggest help and use proper link style
fix error message to also suggest help and use proper link style

DrXyzzy/smc,DrXyzzy/smc,sagemathinc/smc,tscholl2/smc,DrXyzzy/smc,tscholl2/smc,tscholl2/smc,sagemathinc/smc,sagemathinc/smc,DrXyzzy/smc,tscholl2/smc,tscholl2/smc,sagemathinc/smc