compilemessages: Use json.dump with sort_keys option.
compilemessages: Use json.dump with sort_keys option.

This should help make these files stable over time.  Mostly useful for
diffing release tarballs.

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