Bug 10309 - New OPAC theme based on Bootstrap

Bug 10309 - New OPAC theme based on Bootstrap

The goal of this theme is to provide a fully-responsive OPAC which
offers a high level of functionality across multiple devices with varied
viewport sizes. Its style is based on the CCSR theme, with elements of
the Bootstrap framework providing default styling of buttons, menus,
modals, etc.

The Bootstrap grid is used everywhere, but Bootstrap's default
responsive breakpoints have been expanded to allow for better
flexibility for our needs.

All non-translation-depended files are in the root directory of this new
theme:

css, images, itemtypeimg, js, less, and lib. Languages.pm has been
modified to ignore the new directories when parsing the theme language
directories.

This theme introduces the use of LESS (http://lesscss.org/) to build
CSS. Three LESS files can be found in the "less" directory: mixins.less,
opac.less, and responsive.less. These three files are compiled into one
CSS file for production: opac.css. "Base" theme styles are found in
opac.less. A few "mixins" (http://lesscss.org/#-mixins) are found in
mixins.less. Any CSS which is conditional on specific media queries is
found in responsive.less.

At the template level some general sturctural changes have been made.
For the most part JavaScript is now at the end of each template as is
recommended for performance reasons. JavaScript formerly in
doc-head-close.inc is now in opac-bottom.inc.

In order to be able to maintain this structure and accommodate
page-specific scripts at the same time the use of BLOCK and PROCESS are
added. By default opac-bottom.inc will PROCESS a "jsinclude" block:

[% PROCESS jsinclude %]

Each page template in the theme must contain this block, even if it is
empty:

[% BLOCK jsinclude %][% END %]

Pages which require that page-specific JavaScript be inserted can add it
to the jsinclude block and it will appear correctly at the bottom of the
rendered page.

The same is true for page-specific CSS. Each page contains a cssinclude
block:

[% BLOCK cssinclude %][% END %]

...which is processed in doc-head-close.inc:

[% PROCESS cssinclude %]

Using these methods helps us maintain a strict separation of CSS links
and blocks (at the top of each page) and JavaScript (at the bottom). A
few exceptions are made for some JavaScript which must be processed
sooner: respond.js (https://github.com/scottjehl/Respond, conditionally
applied to Internet Explorer versions < 9 to allow for layout
responsiveness), the _() function required for JS translatability, and
Modernizr (http://modernizr.com/, a script which detects browser
features and allows us to conditionally load JavaScript based on
available features--or lack thereof).

Another new JavaScript dependency in this theme is enquire.js
(http://wicky.nillia.ms/enquire.js/), which lets us trigger JavaScript
events based on viewport size.

I have made an effort to re-indent the templates in a sane way,
eliminating trailing spaces and tabs. However, I have not wrapped lines
at a specific line length. In order to improve template legibility I
have also tried to insert comments indicating the origin of closing tags
like <div> or template directives like [% END %]:

</div> <!-- / .container-fluid -->

[% END # / IF ( OpacBrowseResults && busc ) %]

TESTING

Proper testing of this theme is no easy task: Every template has been
touched. Each page should work reasonable well at a variety of screen
dimensions. Pages should be tested under many conditions which are
controlled by toggling OPAC system preferences on and off. A variety of
devices, platforms, and browsers should be tested.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>