add consensus testplan

test/consensus_testplan.md

@@ -0,0 +1,21 @@
+## testplan for consensus
+
+### incorrect data
+
+- wrong signature
+- construct incorrect consensus messages
+
+### timeout
+
+- leader timeout in normal phase
+- new leader timeout in viewchange phase
+- multiple new leaders timeout in a row (m < n/3)
+- two newview messages arrive at similar time
+- a single node stucked at viewchange mode. e.g. new node stucked in view change while others move on
+
+### malicious
+
+- leader broadcasts different blocks in announce phase
+- leader send different subsets of prepared signature in prepare phase
+- new leader doesn't send prepared message from previous view
+- new leader 't send inconsistent announce message from previous view