restore disabled wallet functionalities

[jellegerbrandy]

We already have working modals, and design, for modals to "show the seed" and "send ether" etc.

These are the following modals:

• show Seed
• restore keystore
• send PTI
• send ETH

What needs to be done is:

• un-skip the relevant tests in tests/player.test.js and tests/profile.test.js
• (possibly write more tests for error handling)
• add the relevant buttons on wallet.html - as designed in #164
• prettify the modals themselves if necessary