* add zcash_history.rs with librustzcash Tree wrapper
* Apply suggestions from code review
Co-authored-by: teor <teor@riseup.net>
* Apply changes from code review
* Update zebra-chain/src/primitives/zcash_history.rs
Co-authored-by: teor <teor@riseup.net>
* Apply changes from code review
* Add Entry struct; return Result where needed; add test
* Apply suggestions from code review
Co-authored-by: teor <teor@riseup.net>
* zcash_history: improve naming style with `inner`
* zcash_history: check if block has the correct network upgrade when adding to tree
* zcash_history: test improvements
* zcash_history: split Tree::new into new_from_block and new_from_cache
* zcash_history: move tests to their own file
* remove unneeded empty line in Cargo.toml
Co-authored-by: teor <teor@riseup.net>