iPad location sharing, bugfixes and Android support

I've installed a couple of fixes in the web locations updating code now. It failed to work for about 6 unlucky users due to a little bug which didn't take database replication delays into account. But that's sorted now.

I've also put the 'share location' button on the non-mobile site, so that it can be used on the iPad and other larger devices with GPS. We'll see what effect that has!

The good news is that it seems to work on several Android phones:

• Google Nexus One
• HTC Dream
• HTC Espresso
• Samsung Galaxy S
• Motorola Droid
• LG Ally

It'll probably work on the rest of the new ones with GPS, too.
The new tool buttons are now documented in the manual.