docs: Update new-feature-tutorial.
docs: Update new-feature-tutorial.

This updates the new-feature-tutorial for the recent changes done
in org settings subsystem.

Edited significantly by tabbott, mostly for grammar.

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