Julian Lam 07b846c72d feat: theme changes for
Squashed commit of the following:

commit bbafa08bd7e1753af5adc50e1b01a6939d154907
Author: Julian Lam <julian@nodebb.org>
Date:   Fri Jul 17 15:52:31 2020 -0400

    add trash can icon to delete target button

commit 0e585109e5d19aad31dde13a084dec78b1cc533f
Author: Julian Lam <julian@nodebb.org>
Date:   Fri Jul 17 15:44:29 2020 -0400

    removed refunct 'reporter' dropdown in quick actions

commit 7bc2c0bdbcb42fa322c82c1808cdbbfa7419b1fd
Author: Julian Lam <julian@nodebb.org>
Date:   Fri Jul 17 15:14:35 2020 -0400

    fix: margin in flag report bq

commit eb59fc455c63f67d51f2ae12f06208e5e09a7afc
Author: Julian Lam <julian@nodebb.org>
Date:   Fri Jul 17 15:08:40 2020 -0400

    wip: 
..
bootstrap Use system fonts instead of Robot webfont
modules feat: Taskbar icon colour change + visibility icon
account.less Revert "fix: remove absolute from cover and remove margins, fixes https://github.com/NodeBB/NodeBB/issues/7969"
bootstrap-flipped.css remove link to map file
categories.less fix: using different class name
category.less fix: https://github.com/NodeBB/NodeBB/issues/8465
chats.less https://github.com/NodeBB/NodeBB/issues/8043
flags.less feat: theme changes for
footer.less init
groups.less fix: overflow on long group names,
header.less fix:
helpers.less init
keyframes.less animations for new taskbar
mixins.less Moved "fix-lists" mixin out to core, and added a bit of margin to the right of the chat messages.
mobile.less Revert "fix: remove absolute from cover and remove margins, fixes https://github.com/NodeBB/NodeBB/issues/7969"
noscript.less fix noscript.less
notifications.less missed a couple mixin use cases
outgoing.less closes https://github.com/NodeBB/NodeBB/issues/6029
persona.less alert wont push back topic list
posts_list.less fix: https://github.com/NodeBB/NodeBB/issues/8482
register.less adjust dropdown layout on unread page ()
rtl.less fix: usercard on RTL
search.less feat: quick search changes
style.less fix: https://github.com/NodeBB/NodeBB/issues/7909
tags.less styled tags
topic.less closes https://github.com/NodeBB/NodeBB/issues/7985
topics_list.less alert wont push back topic list
users.less fix: guest size to match users