When adding colors to length tuner, we depend on the window background
color, which can be set by the user, resulting in an unreadable text.
This uses the HSL conversion to detect which shade it should use for the
coloring.
Also adds test cases for round-trip HSL and HSV conversion
Fixes: lp:1814530
* https://bugs.launchpad.net/kicad/+bug/1814530
Due to the implicit floor of the cast from double to unsigned char,
there was a small rounding error in COLOUR4D's WX conversion function.
This fixes the failing tests.
Also make the cast to unsigned char explicit.
This includes:
* Linkage against the Boost unit test libs
* Configuration of the Boost libs
* A place for common generics "extras" for unit test harnesses
including
* A simple way to allow "expected-failure" tests (without
breaking Boost < 1.58, e.g. Ubuntu LTS)
* Moving some simple numeric predicates from the geom tests
to the utils library.
Expand unit test docs to describe the expected failures macro.
Add a few COLOR4D tests, including one with expected failures due
to a pre-existing bug. This will be fixed in a follow-up commit.
Seth Hillbrand
John Beard