Adds contour image PATH/TO/IMAGE CLI command

[christianparpart]

In the spirit of icat FILE integration, contour image FILE should upload given FILE to the terminal and have it rendered at the current cursor position.

People then may chose to alias icat="contour image".

Initially this will transmit Sixels, but ultimatively later utilize the Good Image Protocol once available.

Blockers

• package up libsixel for fedora libsixel/libsixel#11
• libsixel as vcpkg package (Windows platform) libsixel/libsixel#59

[christianparpart]

I doubt libsixel will ever come to Fedora nor be available on vcpkg. Closing in favor of future Good Image Protocol later.