Update variables to be compatible with Bootstrap 3.0.3

Bootstrap 3.0.3 requries a few variables that aren't included in
Drupal Bootstrap subtheme template.  Add them so we can
compile our theme LESS.

Addresses #3551
Basic elements for theme

* Grid
* Navbar styles
* Logo styles
* Colors
* Fonts
* Customize Bootstrap's variables.less

Still to do:

* Create sprites from image assets
* Footer content. Is it better to hard-code this in the theme, or
create blocks?
* Content-type specific pages
* Favicon
* Probably a bunch of other stuff

Note that I'm keeping style.css in the repository for now, for
ease of deployment, but we should just generate this on deployment
once we figure out a good way to do it.

Addresses #3551
Add footer elements to page template

* MSA logo
* MSA shoutout microcopy
* License microcopy
* Footer element styles

The template currently just hard codes these elements and
doesn't print any blocks that may be assigned to the footer region.
In the future, it may be desirable to create custom blocks for these
elements so they can be configured by site admins/builders.

Addresses #3551
Typography styles

* Headings
* Breadcrumbs
* Buttons
* Links

Addresses #3551
Styling and theming for elements on Board page

* Field labels
* Field text
* "Search past and future members" link, styled as button
* Custom node template for Board nodes to allow for 2-column layout.
* Custom rendering for application URL field so it gets its link
  text from the other field.
* Style application URL field as button
* Form inputs
* Form panel headings

Addresses #3551
Board term table styles

Addresses #3551
Make logo and sidebar respond to large size grid

Addresses #3551
Not terrible styles for small displays

The logo could still use a special treatment for smaller displays.

Addresses #3551
Move navbar to top of display on small screens

Addresses #3551
Merge branch '3551-theme' of https://github.com/ghing/onboard_profile into ghing-3551-theme
Theming polish

* Fix selector for removing the top spacing added to the body by
  admin menu.
* Correctly detect if a logo is present to select the width of the
  main container.
* Give the left container a class, sidebar-first-container, instead
  of using its grid class as a selector.

Addresses #3551
Add "Clerk Login" link to user menu

Add login link (links to user/login) with label "Clerk Login" to
user menu.

Addresses #3551
Merge remote-tracking branch 'ghing/3551-theme' into ghing-3551-theme
Add user menu links to feature

I added the menu, but forgot to add the links in
1110e4c63df3f9e00d627b7223c08af43757805c

Addresses #3551
Merge remote-tracking branch 'ghing/3551-theme' into ghing-3551-theme
Add the user menu links to the helper feature

Following up on fe97c7ffc341546b394d01e32d2a7c01a1065096.  I forgot
do git add the onboard_theme_helpers.features.menu_links.inc
file.

Addresses #3551
Merge remote-tracking branch 'ghing/3551-theme' into ghing-3551-theme
Document building theme CSS

* Add bootstrap sources to drush makefile
* Add instructions on building theme CSS to README

Addresses #3551
Hook for adding theme JavaScript

Use this instead of ``scripts[]`` in ``onboard_theme.info`` so we
can have more control of the order in which scripts are added.

For now, use this to load Modernizr.

Addresses #3551
Fix primary button hover colors

Also fix some typos in HTML color codes.

Addresses #3551