Merge pull request #79 from MooseTheBrown/master

Fix qt bindings installation on 64-bit systems + version update to 3.0.1
Update OpenCV Git repository URL (Fixes #80)
Check errors explicitly; don't rely on assert().
Add support for CMAKE_LIBRARY_ARCHITECTURE.
Generate an error if Qt bindings were requested but are not able to be built.
Remove dirs files.
Update debian/compat to 9.
Add support for multi-arch.
Update standards-version.
Let libpsmoveapi3-dev package get shlibs:Depends from libpsmoveapi3 instead of directly.
Add support for debug symbol packages, Qt.

This would be better as two patches, but I'm not sure if it's worth
the overhead to separate them.

Note that I added a Recommends: for libpsmoveapiqt3.  I'm not sure if
that is ideal, but I didn't want to make a separate -dev package just
for libpsmoveapiqt3, and Requires: was a bit limiting.
Tracker: Avoid bogus warning for Exposure_LOW

Thanks to CJ Davies on the mailing list for reporting.
New utility: psmove_dfu_mode

Thanks to Alexander for researching the magic numbers.
Various compiler warning fixes
Prefer local filenames to filenames in the data directory
Merge pull request #84 from kdienes/cmake-patches

Cmake patches
Merge pull request #82 from kdienes/check-errors

Check errors explicitly; don't rely on assert().
Merge pull request #85 from kdienes/debian-packaging

Debian packaging
Calibration data saving in /etc/psmoveapi on Linux

Calibration is saved in /etc/psmoveapi for root user on Linux.
Non-root users read calibration first from local ~/.psmoveapi
directory and then from /etc/psmoveapi if there is no local
calibration data.