Another approach to the index.html and index.js

[fridrich]

This commit is basically compiling the index.html and index.js as resources into the binary. It avoids one to have to install them and bother about finding where they are.

[fridrich]

Now, this would need the xxd resource compiler, but I find that the advantage of having a single binary is great

[mpbraendli]

Hi, I like the idea, even though for development it means changing the HTML incurrs a compile/link cycle, and it makes user-customisation more difficult. But it avoids file availability issues.

Why did you move from C++17 to C++14?

Using xxd -i is cool, I was wondering if we could use od instead, because that's in coreutils, but it'd need more tinkering. So I'm ok with adding xxd as a build-time dependency.

[fridrich]

I moved the C++17 back to the C++14 because originally in the reverted commit I added it only to be able to use std::filesystem::path which is now not needed again. That is why I also restored lower cmake requirement

[fridrich]

Ping?

[mpbraendli]

Thanks for the reminder!