[xml] purify related patches

[Mark Vakoc <thevakoc-xml yahoo com>]

(originally sent using wrong e-mail..)

> While running Purify [Windows] on my application I found some minor problems.
>
> Patches attached.
>
> uri.diff: xmlURIUnescape has an unitialized memory read by reading beyond the
> passed in buffer length
>
> threads.diff [windows] : the thread's (global state) xmlLastError is not
> freed
> on thread termination so there could be a leak or two
>
> If I find anymore I'll send some more patches.
>
> mark

Attachment: uri.diff
Description: uri.diff

Attachment: threads.diff
Description: threads.diff