tools: Remove replacer.
tools: Remove replacer.

This seems to be a complicated wrapper around `sed`.
It's not used anywhere or documented anywhere.  I
assume it was used in some code sweep or something.

See cec45b0ae547c5a81ab463b5d249c2325cfd883f

timabbott/zulip,brainwane/zulip,showell/zulip,punchagan/zulip,brainwane/zulip,eeshangarg/zulip,rht/zulip,eeshangarg/zulip,showell/zulip,rht/zulip,synicalsyntax/zulip,zulip/zulip,brainwane/zulip,punchagan/zulip,synicalsyntax/zulip,shubhamdhama/zulip,timabbott/zulip,shubhamdhama/zulip,synicalsyntax/zulip,shubhamdhama/zulip,synicalsyntax/zulip,eeshangarg/zulip,punchagan/zulip,hackerkid/zulip,kou/zulip,andersk/zulip,rht/zulip,shubhamdhama/zulip,eeshangarg/zulip,showell/zulip,kou/zulip,brainwane/zulip,hackerkid/zulip,shubhamdhama/zulip,synicalsyntax/zulip,punchagan/zulip,shubhamdhama/zulip,brainwane/zulip,andersk/zulip,timabbott/zulip,showell/zulip,rht/zulip,zulip/zulip,brainwane/zulip,rht/zulip,shubhamdhama/zulip,andersk/zulip,timabbott/zulip,hackerkid/zulip,timabbott/zulip,showell/zulip,synicalsyntax/zulip,hackerkid/zulip,andersk/zulip,rht/zulip,brainwane/zulip,hackerkid/zulip,eeshangarg/zulip,timabbott/zulip,synicalsyntax/zulip,zulip/zulip,eeshangarg/zulip,timabbott/zulip,kou/zulip,showell/zulip,zulip/zulip,zulip/zulip,kou/zulip,zulip/zulip,showell/zulip,zulip/zulip,rht/zulip,andersk/zulip,punchagan/zulip,punchagan/zulip,kou/zulip,kou/zulip,hackerkid/zulip,andersk/zulip,eeshangarg/zulip,kou/zulip,hackerkid/zulip,punchagan/zulip,andersk/zulip