Update bitcoingui.cpp
Update bitcoingui.cpp

Fix for nEstimateTime
Kefkius/clams,dooglus/clams,dooglus/clams,Jheguy2/Mercury,robvanmieghem/clams,robvanmieghem/clams,thunderrabbit/clams,nochowderforyou/clams,robvanmieghem/clams,thunderrabbit/clams,robvanmieghem/clams,Jheguy2/Mercury,dooglus/clams,robvanmieghem/clams,Kefkius/clams,Kefkius/clams,dooglus/clams,thunderrabbit/clams,nochowderforyou/clams,Jheguy2/Mercury,nochowderforyou/clams,Jheguy2/Mercury,thunderrabbit/clams,Kefkius/clams,nochowderforyou/clams,Kefkius/clams,nochowderforyou/clams,Jheguy2/Mercury,dooglus/clams,thunderrabbit/clams