Fix on Bug 38829 - Add fractional inches to units

Hi,

My team and I have narrowed down the modification required to make this
happened. We modified MetricField in vcl/source/control/field.cxx to take
in fractional data format (i.e. 1 1/2"), parse and convert to decimal
format and then output it. Since MetricField is used for most dimension
setting textfields in Draw, our change would render all such texfields to
be capable of specifying fractional inches.

However, this is a mere hijack of the parsing of user input, the output
remains in decimal format. There are several considerations involved in
this decision and the most important being that, this change will adhere to
the standardization of the textfields' display without affecting other
functionalities.

Our own preliminary unit tests have shown our change is stable. We
conducted further verifications with tests installed on the system without
a hitch.

How should we move forward with the changes? Do we go ahead and push our
changes to gerrit?

Cheers,
Foo Lai