[book] add autoload section from code and fix sphinx warnings
* drop misleading faq entry since clear explanation can be found in internationalization chapter
* use autodata sphinx directive instead of raw text
* fill empty chapter with autodoc:
- devweb/httpcaching.rst
- devweb/resource.rst
- devweb/views/idownloadable.rst
- devweb/views/wdoc.rst
* use shebang in excerpt to denote shell code
* fix some bad indented docstrings in javascript files
<html><head><!-- dependencies --><scripttype="text/javascript"src="../../data/jquery.js"></script><scriptsrc="../../data/cubicweb.python.js"type="text/javascript"></script><scriptsrc="../../data/cubicweb.js"type="text/javascript"></script><scriptsrc="../../data/cubicweb.compat.js"type="text/javascript"></script><scriptsrc="../../data/cubicweb.dom.js"type="text/javascript"></script><scriptsrc="../../data/cubicweb.htmlhelpers.js"type="text/javascript"></script><scriptsrc="../../data/cubicweb.ajax.js"type="text/javascript"></script><!-- qunit files --><scripttype="text/javascript"src="../../../devtools/data/qunit.js"></script><linkrel="stylesheet"type="text/css"media="all"href="../../../devtools/data/qunit.css"/><!-- test suite --><scriptsrc="cwmock.js"type="text/javascript"></script><scriptsrc="test_ajax.js"type="text/javascript"></script></head><body><divid="main"></div><h1id="qunit-header">cubicweb.ajax.js functions tests</h1><h2id="qunit-banner"></h2><olid="qunit-tests"></body></html>