Log Message:
Upgrade QCAD to version 3.15.5.3

QCAD has been largely rewritten since the previous version
(QCAD 2) was updated in pkgsrc, meaning that the changes are
vast. From the authors website:

    QCAD 3 comes with a new and improved CAD engine which improves
    performance (spatial index) and allows for advanced property
    editing and future extensions (dynamic properties). The other
    major addition is a powerful and complete ECMAScript interface.
    New interactive tools can be developed with a few lines of
    ECMAScript but even entire new applications can be developed
    using QCAD technology. QCAD 3 is also the first QCAD version
    that fully supports the DWG format as well as various different
    versions of the DXF format.

The complete ChangeLog is at http://www.qcad.org/en/changelog