Update JS/CSS dependencies for better CSP compatibility

[koenpunt]

Currently to allow the coverage page to be working correctly it requires a very loose Content-Security-Policy, e.g.:

script-src 'self' 'unsafe-eval'; style-src 'self' 'unsafe-inline';

With the changes in this PR this can be updated to a more restricted:

default-src 'none'; script-src 'self'; img-src 'self'; style-src 'self';

Fixes #50

[koenpunt]

Found out that the sorting in the datatable isn't currently working as expected, but that should be trivial to fix.

[PragTob]

👋

Hi there, thanks for this 💚

I know it's been way too long, but well I first spent my time on "core" simplecov and kinda worked my way here. Sorry for the delay.

I'll see how I'll handle this. I'm not sure if a merge will be the best way, might start over and use your implementation as a guide. But yes this needs to be tackled

Cheers,
Tobi

[PragTob]

Replaced by #89