stats: Change title for Number of Users graph.
stats: Change title for Number of Users graph.

This stat used to have the total number of users, but was changed in f595f4f
to be the number of 2-week actives.

amanharitsh123/zulip,brockwhittaker/zulip,vaidap/zulip,vaidap/zulip,punchagan/zulip,rht/zulip,jrowan/zulip,tommyip/zulip,synicalsyntax/zulip,brockwhittaker/zulip,jphilipsen05/zulip,amanharitsh123/zulip,kou/zulip,j831/zulip,dhcrzf/zulip,Galexrt/zulip,jackrzhang/zulip,punchagan/zulip,vaidap/zulip,synicalsyntax/zulip,andersk/zulip,tommyip/zulip,jackrzhang/zulip,tommyip/zulip,vaidap/zulip,timabbott/zulip,timabbott/zulip,amanharitsh123/zulip,hackerkid/zulip,brainwane/zulip,showell/zulip,rishig/zulip,vaidap/zulip,rht/zulip,Galexrt/zulip,vaidap/zulip,verma-varsha/zulip,rht/zulip,j831/zulip,jrowan/zulip,dhcrzf/zulip,brockwhittaker/zulip,ryanbackman/zulip,dhcrzf/zulip,showell/zulip,kou/zulip,punchagan/zulip,jrowan/zulip,tommyip/zulip,jphilipsen05/zulip,zulip/zulip,jackrzhang/zulip,amanharitsh123/zulip,jphilipsen05/zulip,punchagan/zulip,zulip/zulip,verma-varsha/zulip,rishig/zulip,vabs22/zulip,hackerkid/zulip,brainwane/zulip,zulip/zulip,dhcrzf/zulip,jphilipsen05/zulip,mahim97/zulip,mahim97/zulip,eeshangarg/zulip,andersk/zulip,mahim97/zulip,synicalsyntax/zulip,zulip/zulip,j831/zulip,synicalsyntax/zulip,ryanbackman/zulip,synicalsyntax/zulip,dhcrzf/zulip,showell/zulip,jackrzhang/zulip,brainwane/zulip,rishig/zulip,eeshangarg/zulip,brockwhittaker/zulip,showell/zulip,synicalsyntax/zulip,punchagan/zulip,hackerkid/zulip,christi3k/zulip,vabs22/zulip,brainwane/zulip,eeshangarg/zulip,andersk/zulip,andersk/zulip,shubhamdhama/zulip,hackerkid/zulip,mahim97/zulip,rht/zulip,christi3k/zulip,brainwane/zulip,eeshangarg/zulip,shubhamdhama/zulip,hackerkid/zulip,dhcrzf/zulip,zulip/zulip,vabs22/zulip,timabbott/zulip,andersk/zulip,verma-varsha/zulip,ryanbackman/zulip,amanharitsh123/zulip,verma-varsha/zulip,j831/zulip,kou/zulip,Galexrt/zulip,eeshangarg/zulip,shubhamdhama/zulip,ryanbackman/zulip,kou/zulip,rht/zulip,shubhamdhama/zulip,brainwane/zulip,Galexrt/zulip,rht/zulip,showell/zulip,tommyip/zulip,dhcrzf/zulip,Galexrt/zulip,brockwhittaker/zulip,brainwane/zulip,synicalsyntax/zulip,rishig/zulip,tommyip/zulip,jrowan/zulip,hackerkid/zulip,Galexrt/zulip,christi3k/zulip,timabbott/zulip,ryanbackman/zulip,vabs22/zulip,jrowan/zulip,tommyip/zulip,jackrzhang/zulip,showell/zulip,andersk/zulip,christi3k/zulip,amanharitsh123/zulip,jackrzhang/zulip,showell/zulip,shubhamdhama/zulip,shubhamdhama/zulip,zulip/zulip,hackerkid/zulip,j831/zulip,rishig/zulip,verma-varsha/zulip,rishig/zulip,Galexrt/zulip,jackrzhang/zulip,vabs22/zulip,punchagan/zulip,eeshangarg/zulip,ryanbackman/zulip,j831/zulip,vabs22/zulip,verma-varsha/zulip,kou/zulip,jrowan/zulip,kou/zulip,jphilipsen05/zulip,timabbott/zulip,mahim97/zulip,christi3k/zulip,rht/zulip,eeshangarg/zulip,timabbott/zulip,punchagan/zulip,jphilipsen05/zulip,brockwhittaker/zulip,timabbott/zulip,kou/zulip,shubhamdhama/zulip,christi3k/zulip,andersk/zulip,zulip/zulip,mahim97/zulip,rishig/zulip