Remove 90 char limit

[arshbot]

Yes, BIP-0173 specifies a max 90 char limit for addresses, however bech32 encoding is used outside of bitcoin, specifically in Lightning Network's Bolt11 where the majority of payment requests are encoded in bech32, and whose size is significantly larger than 90 chars most of the time.

Enforcing the limit makes this tool unusable for anything Lightning Network related, I request that the limitation is removed. I can supply the simply PR removing the relevant code

[slowli]

@arshbot Yeah, makes sense. I think it could make sense to think about some "smart" solution (i.e., restricting the input buffer length by default and allowing longer buffers on an explicit opt-in), but I'm quite fine with a simple solution initially.

[arshbot]

I spent some time working on this issue @slowli and decided that the scope of this issue has grown beyond this ticket. Please see the new ticket I've opened up.

#12