fix alignment
remove empty example notebook

looks like it was committed by mistake
allow session_id to be undefined when starting kernel channels
use default kernel name in kernels service

matches sessions API
update font-awesome
genereate css
Merge pull request #6686 from minrk/default-kernel

use default kernel name in kernels service
Merge pull request #6684 from minrk/rm-spreadsheet

remove empty example notebook
remove redundant 'responsive-utilities' from style.less

it's already included in bootstrap.less
Merge pull request #6691 from minrk/rm-bs

remove redundant 'responsive-utilities' from style.less
Merge pull request #6685 from minrk/allow-no-session-id

allow session_id to be undefined when starting kernel channels
Merge pull request #6669 from SylvainCorlay/font_awesome_update

Font awesome update
Merge pull request #6681 from SylvainCorlay/widget_hbox_align

Minor change in widgets.less to fix alignment issue
install local mathjax on Travis

when running the js tests

I'm not sure why loading MathJax from the CDN is falling on Travis,
but it's not happening locally.
Merge pull request #6703 from minrk/install-mathjax-travis

install local mathjax on Travis
Added bootstrap tags css file
Initial upload of cell tagging toolbar
fab css
Bug fixes and address comments from in person review with Brian
Bug fixes and GH review suggestions.