2017-02-16 Germar <github.com/Germar>

* rs.h (LinearFormat)
* rs_dimaligned.cpp (getMeasuredLabel)
* rs_dimdiametric.cpp (getMeasuredLabel)
* rs_dimlinear.cpp (getMeasuredLabel)
* rs_dimradial.cpp (getMeasuredLabel)
* rs_graphic.cpp (getLinearFormat)
* rs_units.cpp (formatLinear)
* rs_units.h (public):
added ArchitecturalMetric using DIN 406 (issue #861)

* qg_dlgoptionsdrawing.cpp (validate):
add warning about unit for length format 'ArchitecturalMetric' must be 'Meter'
