evidence: introduce time.Duration to evidence params (#4254)

* evidence: introduce time.Duration to evidence params

- add time.duration to evidence
- this pr is taking pr #2606 and updating it to use both time and height

- closes #2565

Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>

* fix testing and genesis cfg in signer harness

* remove debugging fmt

* change maxageheight to maxagenumblocks, rename other things to block instead of height

* further check of duration

* check duration to not send peers outdated evidence

* change some lines, onward and upward

* refactor evidence package

* add a changelog pending entry

* make mockbadevidence have time and use it

* add what could possibly be called a test case

* remove mockbadevidence and mockgoodevidence in favor of mockevidence

* add a comment for err that is returned

* add a changelog for removal of good & bad evidence

* add a test for adding evidence

* fix test

* add ev to types in testcase

* Update evidence/pool_test.go

Co-Authored-By: Anton Kaliaev <anton.kalyaev@gmail.com>

* Update evidence/pool_test.go

Co-Authored-By: Anton Kaliaev <anton.kalyaev@gmail.com>

* fix tests

* fix linting

Co-authored-by: Anton Kaliaev <anton.kalyaev@gmail.com>

docs/tendermint-core/using-tendermint.md

@@ -56,7 +56,7 @@ definition](https://github.com/tendermint/tendermint/blob/master/types/genesis.g
   application, and may be left empty to make explicit that the
   application will initialize the validator set with ResponseInitChain.
   - `pub_key`: The first element specifies the `pub_key` type. 1
-  == Ed25519. The second element are the pubkey bytes.
+    == Ed25519. The second element are the pubkey bytes.
   - `power`: The validator's voting power.
   - `name`: Name of the validator (optional).
 - `app_hash`: The expected application hash (as returned by the
@@ -78,7 +78,8 @@ definition](https://github.com/tendermint/tendermint/blob/master/types/genesis.g
       "time_iota_ms": "1000"
     },
     "evidence": {
-      "max_age": "100000"
+      "max_age_num_blocks": "100000"
+      "max_age_duration": "10000"
     },
     "validator": {
       "pub_key_types": [