fix(wallet): support uppercase payment requests

[mrfelton]

Description:

Add support for uppercase payment requests.

I've patched bolt11 to support this. See bitcoinjs/bolt11#12

Motivation and Context:

Fix #1266

How Has This Been Tested?

• Convert a payment request to all uppercase and verify it can be used as expected.
• Verify normal payment requests continue to function as normal

Types of changes:

Bug fix

Checklist:

• My code follows the code style of this project.
• I have reviewed and updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes where needed.
• All new and existing tests passed.
• My commits have been squashed into a concise set of changes.

[coveralls]

Coverage decreased (-0.5%) to 18.663% when pulling 49e7b6e on mrfelton:fix/uppercase-bech32 into f33c5fd on LN-Zap:master.

[coveralls]

Coverage decreased (-0.5%) to 18.663% when pulling 49e7b6e on mrfelton:fix/uppercase-bech32 into f33c5fd on LN-Zap:master.

[coveralls]

Coverage decreased (-0.5%) to 18.663% when pulling 49e7b6e on mrfelton:fix/uppercase-bech32 into f33c5fd on LN-Zap:master.

[JimmyMow]

Tested ACK 49e7b6e