about:history enhancements

[bsclifton]

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).
• styles closer match the mockup; NOTE: style updates are to sortableTable (this may affect search engine page and payments page)
• text no longer wraps; properly handles overflow
• updated search box
• sortable table now accepts a column type of "cell", allowing for custom controls to be passed rather than html
• delete buttons are stubbed out, ready to be implemented
• will be implementing multi-select soon

Fixes #4072
Fixes #3996

Introduces tests for about:history

Auditors: @bradleyrichter @bbondy

Screenshot:

[bbondy]

?

[bbondy]

++, just maybe flesh out the TODO more.
Great testss

[luixxiul]

The table onabout:preferences#search was styled too, which was intended?

[bsclifton]

@luixxiul good catch- yes, it was intended... but unfortunately I didn't put a fix in for the headers.
Captured this with issue #4493

[bradleyrichter]

time column should be fixed width, with no wrap:

[bradleyrichter]

column headers should be forced to vert-align center