Support always on colors

[Shadab Zafar]

I'm using dbg() in a test that runs via ctest which prevents any colors from appearing - as ctest buffers stdout so it has the option of not showing any output if the tests passed.

Running the test binary without ctest gives proper colors.

Having a way to enable coloring regardless of isatty would be great. Something like #DBG_MACRO_COLOR_ALWAYS (akin to grep --color=always).

[Alice Carroll]

Related to #105

[David Peter]

Sounds like a good idea!

Something like #DBG_MACRO_COLOR_ALWAYS (akin to grep --color=always).

👍