Remove old bootstrap styles

[breezewish]

A little clean up to make page layouts behavior more compatible with latest Bootstrap documentation.

[smcgregor]

How thoroughly have you tested this? I am prioritizing my PR queue processing and this one will take time to confirm there are no unintended consequences.

[breezewish]

At least login and settings page is OK. I didn't found significant layout issues currently. In fact this commit remove inconformity between the project and bootstrap.

[smcgregor]

I think this PR increased the effective line height? There is some extra whitespace at the top of the injected view.

[breezewish]

@smcgregor OK, in injected view, bootstrap.css is not imported, so the margin of <p> becomes bigger.

How about creating a stylesheet specifically for injected view (not for all), includes basic typography styles? Typography styles can be grabbed from bootstrap or any other suitable libraries.

[smcgregor]

This can be added here: https://github.com/privly/privly-applications/blob/master/shared/css/injected/injected.css

Do you have a suggested stylesheet?