Property testing for Host Interface functions

[csgui]

Clarity functions to be addressed:

### Tasks
- [ ] at-block
- [x] get-burn-block-info?
- [ ] as-contract
- [x] get-block-info?
- [x] print

Already completed:

### Completed Tasks
- [x] ft-mint?
- [x] ft-transfer?
- [x] map-delete
- [x] map-get?
- [x] map-insert
- [x] map-set
- [x] nft-get-owner?
- [x] nft-mint?
- [x] nft-transfer?
- [x] stx-account
- [x] stx-burn?
- [x] stx-get-balance
- [x] stx-transfer?

[Acaccia]

Nft functions done in #394