File UNITS > contains assignments for automatic conversion to MKS
metric units.  Usage example:  5*FT + METER + CM; simplifies to
2.534*METER .

Erroneously dimensionally inhomogeneous expressions are revealed by
uncollected terms.  For example, 5*FT + SECOND;  
does not simplify to one term.

The supplied conversions comprise a rather complete set, but it should
be clear how to supplement them or produce an analagous set for
conversion to other units.

Send suggestions to STOUTE.