Some OS X maintenance

 * Fixed OS X bugs: animated GIF previews, document icons, app icon drag-and-drop, and dock behaviour.
 * Fixed 'Test Play From Here' being broken in Sugarcane
 * Altered the About box text a bit.
 * Reorganised the locations of icon files in the repository.
Four small tweaks

* Made further About Box alterations.
* Sugarcane: The #sidebar is now position:absolute instead of
position:fixed, thus fixing an iOS zoom-in display bug.
* Fixed the bug where the Snap to Grid state wasn't being correctly
loaded from .tws files.
* The Build Story dialog's default directory is now the current build
destination (if any) rather than just the last used working directory.
Altered the Proofing Copy code

The Proofing Copy code is officially not a supported feature anymore,
but I decided to throw in some extra syntax formatting anyway.

Also fixed the Restart link in Sugarcane not overwriting hash URLs.
Made the continued line syntax less strict

Now, the continued line syntax will still work even if some lone
whitespace separates it and the line break. This is a deviation from the
C tradition, but it should save some confusion.

Also made the parameter() variable coerce a falsy argument to 0, so you
can just write parameter() to receive the first argument.

Also tweaked the README.
previous() alterations

previous() now returns "" when run in the first visited passage. This
allows not previous() to be used to determine if it's the first move.

Also, links whose code passage titles evaluate to "" are now printed as
broken links instead of external links.
Link CSS simplification + header alteration

* Altered the header link CSS to simply use ".passage a", which covers
internal links, external links, back, return, and HTML external links.
The example stylesheet CSS has been altered to use this same
formulation, too.
* Targets can now put the string "STORY" (in quotes) in their HTML code
to have the story's storeArea divs inserted there at compile time
instead of being merely appended. All built-in headers now use this.
Fixed tag CSS in Jonah???

So, as you may have noticed, tag CSS doesn't really work in Jonah - past
passages don't retain their styles when advancing to future passages.
So, I've reworked the entire tag CSS mechanism for Jonah. Instead of
swapping #tagCSS's contents every passage change, it instead adds
[data-tags] selectors to the tagged stylesheets' code, and concatenates
them all into #tagCSS at startup.

The [data-tags] selector injection process is as follows. For each
selector in a style rule:
if selector has ".passage":
change to ".passage[data-tags~=tag]"
else if selector has "body":
change to "body[data-tags~=tag]"
else prepend "body[data-tags~=tag]"
This has the following effects, given what we know about the data-tags
attribute: rules for a .passage are kept for past passages, but rules
for, say, the page background, only exist when the tag is "in the
present" - when the present passage also has that tag.

This uses the CSS parser code from
http://code.google.com/p/google-caja/source/browse/trunk/src/com/google/caja/plugin/
under Apache License 2 (which I am told is MIT compatible).

This commit renders the "transition" tag non-functional for the moment.
An upcoming commit should reinstate it.
Four small tweaks, again

* Added position:relative to #passages.
* The Jonah toolbar no longer appears if Undoing is off, and the
"bookmark to here" link no longer appears if bookmarking is off.
* Custom scripts now have access to the interval used by
scrollWindowTo(), in the variable scrollWindowInterval.
* Copy-pasting passages in the story map now alters the pasted passage's
name to be unique.
Late bugfixes

* Re-added default transition CSS overriding in Jonah.
* Fixed the bookmark href being created too late in Sugarcane, producing
incorrect state serialisation.
* Fixed some implicit globals.
* Fixed Jonah's restart link not clearing the URL hash.
* Fixed pasted widgets' names having numbers appended unnecessarily.
Windows 1.4.0 release

* Output HTML files now print the Twine version in the license instead
of having a static version for each header.
* Fixed some version numbers.
Merge pull request #94 from webbedspace/master

Imminent 1.4.0 release