Improve UX by explaining reserve for fees

[moneyball]

A new users is unlikely to understand why "can send" and "can receive" does not add up to "capacity." I would suggest adding explanations in the UI about why some coins are held back for on-chain fees, a reserve, etc.

[moneyball]

@Roasbeef informed me: "There's a portion to fees for the commitment transaction (to be solved in BOLT 1.1, we'll have minimal fees on commitment, then cpfp to close) and the reserve (1% by default, used to ensure skin in the game at all times to ensure no costless breach attempts)"

It would be great to inform the user of this in the UI in a user-friendly fashion.

[MichelKansou]

Or even better to add mini introduction ( multiple slides ) for first time users that explain each section here's an example of a friendly way to inform user https://dribbble.com/shots/5592262-Supertext-App-Tutorial