Document that CPubKey.IsValid() is consensus critical
Document that CPubKey.IsValid() is consensus critical

Conflicts:

	src/key.h

robvanmieghem/clams,robvanmieghem/clams,nochowderforyou/clams,Kefkius/clams,thunderrabbit/clams,thunderrabbit/clams,nochowderforyou/clams,thunderrabbit/clams,Jheguy2/Mercury,Kefkius/clams,robvanmieghem/clams,Jheguy2/Mercury,Jheguy2/Mercury,dooglus/clams,nochowderforyou/clams,robvanmieghem/clams,Kefkius/clams,nochowderforyou/clams,Kefkius/clams,nochowderforyou/clams,dooglus/clams,thunderrabbit/clams,Kefkius/clams,thunderrabbit/clams,dooglus/clams,Jheguy2/Mercury,dooglus/clams,Jheguy2/Mercury,robvanmieghem/clams,dooglus/clams