Author: Colin Chambers
MDL-36534 Quiz: Group question type unit fields
http://git.moodle.org/gw?p=moodle.git;a=commit;h=c4b2600d4b23c416ceaeade6e0da0d0fd26ec3d3
http://github.com/moodle/moodle/commit/c4b2600d4b23c416ceaeade6e0da0d0fd26ec3d3
+ 2.5 en [mustbenumeric,qtype_calculated]
+ 2.5 en [mustnotbenumeric,qtype_calculated]
+ 2.5 en [units,qtype_numerical]
+ 2.5 en [unitx,qtype_numerical]
- 2.5 en [unithdr,qtype_numerical]