Use <PRE> element in storeArea to avoid character escaping issues

[BobMcElrath]

Justin Case notes that adding a <pre> inside the <div> used to store tiddlers in the storearea fixes the problem with whitespace on IE. But we can go one step further and also remove the \n and \ escaping if we do this.

This has the added benefits of making a TW readable to text-only browsers, javascript-disabled browsers, and search engines.

The IE error is that upon saving, IE compresses a sequence of multiple spaces into one space.

[UdoBorkowski]

See also  this discussion

[MartinBudden]

IE collapses multiple instances of a white space character into a single instance when loading <div>s. (Note this happens on loading, not saving.)

(Split out of ticket #8.)

[JeremyRuston]

Implemented in changeset:1040

[JeremyRuston]

Fixed in changeset:1811