Previously: table cells had no padding, which caused a visual collapse
(cell content was too close to cell neighbors). Table header rows had
dark blue background and black letters.  Tables had no space between
them and following paragraphs.

Changes:
* added 5px padding to cell contents
* changed header row background to gray-ish (I considered switching text
  color to white, but it didn't look good)
* 15px margin on the bottom of the tables (similarly to bottom margin
  used by paragraph style).

add missing bracket

Upgrade bootstrap

Conflicts:
	css/swc-bootstrap.css
	css/swc.css

Join CSS from site and lessons

As per swcarpentry/lesson-template#140, but only the core CSS
changes.

-   Remove extra space before title of boxes
-   Remove background color of boxes when printing
-   Add "Input", "Output" and "Error" tips for code blocks
    when printing
-   Avoid duplicate lines

and "learning objectives" box.

The workshop template is mostly plain bootstrap, so getting it work
alongside the site CSS seems mostly straightforward. We only need to
add in a .workshop class to the body, and a .card class to the
.container in the workshop. Everything else is bootstrap content.

This commit also removes the banner.html include since this did not
seem to be removed in the main site, but was referenced in the CSS.
Removing it makes it clear the .banner class is only needed in the
workshop, not here.

* add Country drop down select
* add Gender

~~~
$ for file in $(grep -r -l 'bootcamp' .); do sed -i 's/bootcamp/workshop/g' $file; done
$ for file in $(grep -r -l 'boot camp' .); do sed -i 's/boot camp/workshop/g' $file; done
~~~

and others minors changes.

Close #240.

Rewriting novice shell lesson so that everything refers to Nelle instead of Vlad.

- Improve to handle err class
- Improve pandoc support

The CSS was add at our main CSS and remove from printing:

- Logo at header
- GitHub ribbon
- Footnote

Close #561.

Use h2 tag for "subtitle" will break any tool used to convert HTML
for another format. This commit replace h2 with span and rely on
CSS for have the same look.

Add GitHub Ribbon to our lessons

- For small screen, preserve margin.
- Use css-beautify

Backport of 9a19e91 from swcarpentry/site.

All credits to Abigail Cabunoc <abigail.cabunoc@oicr.on.ca>
for the awesome work with CSS.

* #462

* responsive for smaller screens
* move menu over more - click will always open menu
* #462