Use a completely custom usage mesage for plain --help
Use a completely custom usage mesage for plain --help

Keep argparse in place for --help <TOPIC>, but try to make that match
the customised short help as much as possible.

beermix/letsencrypt,Bachmann1234/letsencrypt,Jonadabe/letsencrypt,tyagi-prashant/letsencrypt,fmarier/letsencrypt,rutsky/letsencrypt,armersong/letsencrypt,bsmr-misc-forks/letsencrypt,g1franc/lets-encrypt-preview,PeterMosmans/letsencrypt,vcavallo/letsencrypt,stweil/letsencrypt,mitnk/letsencrypt,rutsky/letsencrypt,jmaurice/letsencrypt,letsencrypt/letsencrypt,Jadaw1n/letsencrypt,Bachmann1234/letsencrypt,bsmr-misc-forks/letsencrypt,hsduk/lets-encrypt-preview,stewnorriss/letsencrypt,lbeltrame/letsencrypt,ghyde/letsencrypt,DavidGarciaCat/letsencrypt,lbeltrame/letsencrypt,rugk/letsencrypt,vcavallo/letsencrypt,lmcro/letsencrypt,TheBoegl/letsencrypt,brentdax/letsencrypt,hlieberman/letsencrypt,jmaurice/letsencrypt,BKreisel/letsencrypt,tdfischer/lets-encrypt-preview,PeterMosmans/letsencrypt,ahojjati/letsencrypt,sjerdo/letsencrypt,ruo91/letsencrypt,jtl999/certbot,letsencrypt/letsencrypt,BillKeenan/lets-encrypt-preview,thanatos/lets-encrypt-preview,mitnk/letsencrypt,deserted/letsencrypt,stewnorriss/letsencrypt,jsha/letsencrypt,rlustin/letsencrypt,hsduk/lets-encrypt-preview,luorenjin/letsencrypt,ghyde/letsencrypt,ahojjati/letsencrypt,hlieberman/letsencrypt,Jadaw1n/letsencrypt,skynet/letsencrypt,twstrike/le_for_patching,dietsche/letsencrypt,sjerdo/letsencrypt,thanatos/lets-encrypt-preview,piru/letsencrypt,rlustin/letsencrypt,DavidGarciaCat/letsencrypt,Jonadabe/letsencrypt,sapics/letsencrypt,beermix/letsencrypt,BillKeenan/lets-encrypt-preview,kevinlondon/letsencrypt,sapics/letsencrypt,mrb/letsencrypt,martindale/letsencrypt,kuba/letsencrypt,fmarier/letsencrypt,g1franc/lets-encrypt-preview,brentdax/letsencrypt,mrb/letsencrypt,modulexcite/letsencrypt,BKreisel/letsencrypt,ruo91/letsencrypt,jsha/letsencrypt,piru/letsencrypt,dietsche/letsencrypt,martindale/letsencrypt,goofwear/letsencrypt,Hasimir/letsencrypt,solidgoldbomb/letsencrypt,jmhodges/letsencrypt,skynet/letsencrypt,kuba/letsencrypt,bestwpw/letsencrypt,riseofthetigers/letsencrypt,stweil/letsencrypt,VladimirTyrin/letsencrypt,jmhodges/letsencrypt,solidgoldbomb/letsencrypt,Sveder/letsencrypt,wteiken/letsencrypt,jtl999/certbot,xgin/letsencrypt,luorenjin/letsencrypt,VladimirTyrin/letsencrypt,rugk/letsencrypt,TheBoegl/letsencrypt,tdfischer/lets-encrypt-preview,armersong/letsencrypt,kevinlondon/letsencrypt,goofwear/letsencrypt,twstrike/le_for_patching,wteiken/letsencrypt,lmcro/letsencrypt,Hasimir/letsencrypt,deserted/letsencrypt,tyagi-prashant/letsencrypt,modulexcite/letsencrypt,riseofthetigers/letsencrypt,bestwpw/letsencrypt,xgin/letsencrypt,Sveder/letsencrypt