[request] Remove Boost::math_c99 dependency

[philippremy]

Currently the project requires Boost::math_c99 to be available. I would propose to change this dependency to just Boost::math.

I don't think the project actually uses the c99 functions anywhere (it only uses Boost::math), as I don't see that the relevant header is included anywhere (which would be #include <boost/math/tr1.hpp>).

I stumbled across this when trying to switch the AliceVision embedded dependency building process from b2 to CMake for Boost. As it turns out, the CMake build system neither can build the math_c99 module nor informs the user that it is missing from the installation 😅.

I am currently waiting for an answer regarding this (boostorg/math#1329). Nevertheless, it currently makes CCTag unusable for people who built their Boost with CMake.

[simogasp]

It comes from #168, something to do with vcpkg.
If we can safely remove it I'm all for it

[philippremy]

At least on Linux and macOS this worked fine (no dependency on mth_c99). I do not have a Windows machine available right now, so I can't test that. Will try to set-up a VM and see what can be done for vcpkg, if it is an issue after all.

EDIT:

I quickly scanned through the header related to sign.hpp, and I honestly don't see where it calls out to any non-header only function. So theoretically that should not cause a linker issue... but as a long-term Unix user, I don't know what MSVC might do in terms of voodoo-magic here...