Convertions and wtf interface

I do not know Ruby and I cannot manage to install this package,
so I implemented the commands I would like as a standalone
program in Python.

!oz, !lb (and !lbs), !inch, !ft, !yard, !mile, !length and !°F
offers converts from that their names implies to a unit
in the metric system that is must corresponding to the
unit at the from-side of the convertion. !length converts
a length of a person expressed in feets and inches to
centimeters.

!am and !pm converts time optionally with a date to
from US/Pacific to UTC. !am and !pm only excepts
12-hour clocks and !am and !pm is used for specifying
that the time is before midday and after midday respectively.
If no date is specified 24:00 is prefered over 00:00 in the
output, which is in 24-hours.

The commands uses American formats as input, however
comma is not used for group of 3 separation, but rather
as a decminal put just as a dot.
The output is formated with comma as decimal point,
minus (not hyphen) for negative values, blanks space
for group separation. Time is formated HH:MM and HH:MM:SS
and dates are formatted yyyy-(mm)mmm-dd (so that cannot
be misinterpreted, the month is printed both numerically
and with three letters.)

!wtf uses the command `wtf` (requires the package wtf)
and is used just like `wtf` (but with a bang) and translates
abbreviations to words that you can understand.