Resolve "Use Conan to build Sight"

What does this MR do?

• This MR add conan support in sight
• A temporary conan registry is used for the moment: Artifactory
• All conan package are available on gitlab Conan group
• A new build option is available in sight: USE_CONAN

How to test it?

If you do not have conan installed:

pip3 install conan

Then:

> ninja

Data

no required data

Additional tests to run

• Build on Windows
• Build on Linux

Closes #123 (closed), #148 (closed)