* Added extra message types
* Add send functions for new message types
* Store original value message received from proposer
* Modify handle_value for optimized broadcast
* Modify handle_echo for optimized broadcast
* Add handle_echo_hash function for optimized broadcast
* Add handle_can_decode function for optimized broadcast
* Fixes handle_ready and send_echo functions:
1) Modify handle_ready function for optimized broadcast
2) Modify send_echo function to send `Echo` messages to different subset of nodes from
handle_value and handle_ready functions
* Remove value_message and fix typos
* Add functions for filtering all_ids
* Separate send_echo to send_echo_left and send_echo_remaining
* Rename pessimism_factor to fault_estimate
* Remove redundant bools from Broadcast struct
* Fix multiple counting of nodes who sent both `Echo` and `EchoHash` by changing
`echos` map structure
* Allow conflicting `CanDecode`s from same node
* Fix left and right iterators for `Echo` and `EchoHash` messages
* Fixes bugs in left and right iterators and adds additional checks in handle
functions
* Change can_decodes to BTreeMap<Digest, BTreeSet<N>> and fix send_can_decode
* Minor fixes
* Modify send_echo_remaining to take a hash parameter
* Fix bug in left and right iterators.
* Excluding proposer in iterator led to infinite loop when our_id == proposer_id
* Fix bug in handle_echo and compute_output
* send_can_decode call in handle_echo returned early
* compute_output needed `N - f` full `Echo`s to decode
* Refactor `echos` map to take an EchoContent Enum for `Echo` and `EchoHash` messages
* Run rustfmt
* Refactor to avoid index access and multiple map lookups
* Fix comments and minor refactorings.
* Add an`AllExcept(BTreeSet<N>)` type to `Target` enum to enable sending messages
to non-validators from Broadcast.
* Use `Target::AllExcept` in Broadcast to send `Echo` messages to all non-validator nodes.
* Add `AllExcept(_)` match arms for `Target` match expressions.
* Rename `AllExcept` parameter from `known` to `exclude`.
* Modify send_can_decode to send to all nodes who haven't sent an `Echo`.
* Update docs for broadcast
* Improve formatting and add comments for broadcast docs.
* Fix formatting.
* Allow for sending multiple `CanDecode` messages with different hashes.
* Fix comments.
* Fix bug in sending `Echo`s when node has not received `CanDecode`.
Andreas Fackler
Pawan Dhananjay
Andreas Fackler
Demi Marie Obenour