mypy: Migrate templatetags/app_filters.py to python3.5 annotations.
mypy: Migrate templatetags/app_filters.py to python3.5 annotations.

dhcrzf/zulip,punchagan/zulip,jackrzhang/zulip,rishig/zulip,tommyip/zulip,showell/zulip,hackerkid/zulip,timabbott/zulip,tommyip/zulip,hackerkid/zulip,andersk/zulip,punchagan/zulip,rishig/zulip,jackrzhang/zulip,brainwane/zulip,hackerkid/zulip,dhcrzf/zulip,shubhamdhama/zulip,andersk/zulip,andersk/zulip,shubhamdhama/zulip,jackrzhang/zulip,tommyip/zulip,eeshangarg/zulip,kou/zulip,eeshangarg/zulip,shubhamdhama/zulip,kou/zulip,eeshangarg/zulip,showell/zulip,rishig/zulip,synicalsyntax/zulip,zulip/zulip,shubhamdhama/zulip,jackrzhang/zulip,tommyip/zulip,rht/zulip,kou/zulip,rishig/zulip,kou/zulip,andersk/zulip,andersk/zulip,timabbott/zulip,timabbott/zulip,shubhamdhama/zulip,eeshangarg/zulip,hackerkid/zulip,dhcrzf/zulip,rht/zulip,zulip/zulip,kou/zulip,rht/zulip,timabbott/zulip,zulip/zulip,showell/zulip,brainwane/zulip,punchagan/zulip,brainwane/zulip,synicalsyntax/zulip,dhcrzf/zulip,tommyip/zulip,dhcrzf/zulip,shubhamdhama/zulip,eeshangarg/zulip,zulip/zulip,synicalsyntax/zulip,punchagan/zulip,synicalsyntax/zulip,kou/zulip,eeshangarg/zulip,kou/zulip,rishig/zulip,synicalsyntax/zulip,shubhamdhama/zulip,rht/zulip,timabbott/zulip,rht/zulip,timabbott/zulip,tommyip/zulip,eeshangarg/zulip,andersk/zulip,timabbott/zulip,andersk/zulip,synicalsyntax/zulip,punchagan/zulip,zulip/zulip,brainwane/zulip,brainwane/zulip,brainwane/zulip,punchagan/zulip,zulip/zulip,synicalsyntax/zulip,punchagan/zulip,showell/zulip,jackrzhang/zulip,showell/zulip,dhcrzf/zulip,dhcrzf/zulip,rishig/zulip,hackerkid/zulip,showell/zulip,rishig/zulip,showell/zulip,brainwane/zulip,rht/zulip,jackrzhang/zulip,hackerkid/zulip,tommyip/zulip,zulip/zulip,jackrzhang/zulip,hackerkid/zulip,rht/zulip