test size, vertical and horizontal precision values in LOC records
Fix default size, horizontal and vertical precition values for LOC records.

Default values in RFC 1876 are in meters but the old code used
the numerical value as centimeters.
Fix vertical precision parsing for LOC records.

Vertical precision value was ignored if the optional 'm' (unit)
was missing at the end of input and rest of the input was ignored.
Merge pull request #48 from spacekpe/loc-fix

Fix issue #47 - LOC record parsing