Again, not generic enough functionality to keep in TagRegistry.

Another responsibility that doesn't belong to TagRegistry.

TagRegistry doesn't need to deal with this stuff that's only used
in one place.  The Ext.define configs are only needed in Js::Class
and nowhere else.

Instead of prefixing each static method with "self.", use this
Ruby trick to place all these methods into the 'eigenclass'.

Add a generic #tags method to TagRegistry and do the filtering in
Web::ClassIcons instead.

To determine which icon to used when multiple possibilities.

For now primarily using this to choose the Singleton icon over
Component.

The @class_icon field is now a hash, containing three icons:

 * large - used in class header
 * small - used in tree, tabbar, search
 * redirect - used in search (for alternateClassName)

The Web::ClassIcons takes care of generating all the neccessary CSS.

Copy the files over to class_icons/ dir like the member icons
are copied to member_icons/.  Additionally the @class tag now
defines the default icon.

Similarly also generate CSS for the icons.

This change only deals with class icons in class header (icons in
tree and search are to do).

The ClassIcons class was separated already and this class doesn't
directly deal with icons.  Instead its primary purpose is to provide
the data for the class tree.

Use it in @component and @singleton to define a CSS class name for
the tag that's used for the class instead of the default.

Eliminate the hard-wired icon rendering of class header.

Though the CSS and icons themselves are still hard-wired.

Instead of checking for cls.inherits_from("Ext.Component") when
generating class icons, we can simply check if the class has the
component tag.

Process::Components takes care of auto-detecting components, so one
rarely needs to actually use @component tag.

Just doing things in more conventional way.

Don't assume that the params array is always present.  Even for methods.

Fixes #494

Convert latin1 escape sequences into UTF-8.  By default they resulted
in ASCII-8BIT (binary) encoding, which wasn't compatible with UTF-8,
resulting in error.

Added wrapper encoding method to cope with Ruby 1.8 which has no
builtin encodings support.

The tests file is now also a pure ASCII file, so no funky encoding-stuff
happens there.

Fixes #491

To handle the more complex nesting logic of the guide headings
and rendering of HTML, keeping the GuideToc class itself a lot cleaner.

It's a list, and should me marked up accoringly.

Turn GuideToc into instantiable class, so we can make use of
instance variables, refactor the logic into several helper methods and
avoid passing lots of arguments around.

Add tests for --guides-toc-level=1, 2, 3.

To be named more similarly with --guides option.

Improve the docs of the option - shorten lines and make the effect
of different argument values plain obvious.

The new `--guide-toc-level` option, which defaults to 2, controls what
heading levels will appear in guides' tables of contents. Specifying
`--guide-toc-level=N` will result in headings at or above <hN> being
included in all guides' TOCs. Choosing a `guide-toc-level` of 1 disables
the TOC entirely.

DeprecatedTag: fix typo in message

Fixed typo in README.md: Mediawiki → MediaWiki

Update README.md

So the logic for rendering the HTML is contained in one spot.

Avoiding passing it to almost every method.

We can now also implement an is_new? method that initializes the
lookup hash by itself when needed.