Used the following `sed` command and manually verified the unstaged
changes. Special cases that were not committed included external links
to Wikipedia which are case-sensitive, links specific lines in code, a
link to a title with a slash that had to be cleaned up, and links to
citations on the BIP repository that contain an underscore.
```
sed -E -i '
s/(\[\[[^][]*#)([^]|]*)(\||\]\])/\1\L\2\E\3/g
:again
s/(\[\[[^][]*#)([^]|]*)([: _]+)([^]|]*)(\||\]\])/\1\2-\4\5/g
t again
' bip-0*mediawiki
```
```
sed -z -i 's/Author: /Authors: /' bip-0*.md
sed -z -i 's/Author: /Authors: /' bip-0*.mediawiki
```
Also align correctly in case of multiple authors.
