chore(task aliases): trigger web server on dev alias

As almost all the times we're triggering webserver and dev tasks in
parallel, it's better to do so by using a single command, so I created a
new connect target with keepalive set to false. This way we're able to
trigger the webserver together with the watch task.
fix(table): make contextual cells have higher specifity

When contextual classes were used together with a table that has
striped rows, the stripes background were winning.

Fixes #38