plt-racket 6.0

Closes #27053.
youtube-dl 2014.02.27

Also add PyPI request/warning.

Closes #27052.
mongodb: dyn suffix no longer needed for extrapath

Closes #27054.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
ettercap: move conditional into method
add Formula[]

Closes #26930
add audit for Formula.factory
avidemux: use Formula[]
yap: use Formula[]
bind: use Formula[]
boost: use Formula[]
cadaver: use Formula[]
calc: use Formula[]
cfengine: use Formula[]
cgdb: use Formula[]
clasp: use Formula[]
curl: use Formula[]
cloog: use Formula[]
coq: use Formula[]
dos2unix: use Formula[]
dsniff: use Formula[]