Rewrite template's data format to use json

[homeisfar]

Snap2HTML, being a Windows-only program, gets to make certain assumptions about the files it's expected to handle. This also means it can use a bespoke data format to interpret in its html, delimited by *.

The problem for us Linux users is that a file can basically have anything but / and \0 as a character. And while I have no intention to handle \n in filenames, * is problematic since it's the delimiter. This can cause issues like files apparently missing in the manifest. I don't think there's any working around this without resorting to a well-specified data format, and json is the best, most readily available option.

[cxplay]

I've been waiting for your work.😘