Faster access to frequently used tools on mobile

We've made a few changes to the mobile app to make the Tools menu easier to use, especially on smaller screens.

• Pin two tools to the nav bar for quicker access to the bits you use most
• Find Payouts in the Tools menu so it's easier to get to
• Use the Tools menu more easily on smaller screens after a few layout tweaks

This is an experiment, so it might not stick around. We love to hear your feedback, so drop Sid a message (about this, or anything else).