More to proofread

[PythonCHB]

Here are a few more:

• [x] https://github.com/UWPCE-PythonCert/PythonCertDevel/blob/c_1_revision/source/exercises/mailroom.rst

• [x] https://github.com/UWPCE-PythonCert/PythonCertDevel/blob/c_1_revision/source/exercises/kata_fourteen.rst

• [x] https://github.com/UWPCE-PythonCert/PythonCertDevel/blob/c_1_revision/source/exercises/mailroom-oo.rst

[PythonCHB]

note there are checkboxes you can use to note when you've done one.

[PythonCHB]

This has been done (and mailroom re-structured to be a bit anyway)