docs: Added evidence client docs (cosmos#10355)

<!--
The default pull request template is for types feat, fix, or refactor.
For other templates, add one of the following parameters to the url:
- template=docs.md
- template=other.md
-->

## Description

Closes: cosmos#10289

<!-- Add a description of the changes that this PR introduces and the files that
are the most critical to review. -->

---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

x/evidence/spec/07_client.md

@@ -0,0 +1,182 @@
+# Client
+
+## CLI
+
+A user can query and interact with the `evidence` module using the CLI.
+
+### Query
+
+The `query` commands allows users to query `evidence` state.
+
+```bash
+simd query evidence --help
+```
+### evidence
+
+The `evidence` command allows users to list all evidence or evidence by hash.
+
+Usage:
+
+```bash
+simd query evidence [flags]
+```
+To query evidence by hash
+
+Example:
+
+```bash
+simd query evidence "DF0C23E8634E480F84B9D5674A7CDC9816466DEC28A3358F73260F68D28D7660"
+```
+
+Example Output:
+
+```bash
+evidence:
+  consensus_address: cosmosvalcons1ntk8eualewuprz0gamh8hnvcem2nrcdsgz563h
+  height: 11
+  power: 100
+  time: "2021-10-20T16:08:38.194017624Z"
+```
+
+To get all evidence
+
+Example:
+
+```bash
+simd query evidence
+```
+Example Output:
+
+```bash
+evidence:
+  consensus_address: cosmosvalcons1ntk8eualewuprz0gamh8hnvcem2nrcdsgz563h
+  height: 11
+  power: 100
+  time: "2021-10-20T16:08:38.194017624Z"
+pagination:
+  next_key: null
+  total: "1"
+```
+
+## REST
+
+A user can query the `evidence` module using REST endpoints.
+
+### Evidence
+
+Get evidence by hash
+
+```bash
+/cosmos/evidence/v1beta1/evidence/{evidence_hash}
+```
+
+Example:
+
+```bash
+curl -X GET "http://localhost:1317/cosmos/evidence/v1beta1/evidence/DF0C23E8634E480F84B9D5674A7CDC9816466DEC28A3358F73260F68D28D7660"
+```
+Example Output:
+
+```bash
+{
+  "evidence": {
+    "consensus_address": "cosmosvalcons1ntk8eualewuprz0gamh8hnvcem2nrcdsgz563h",
+    "height": "11",
+    "power": "100",
+    "time": "2021-10-20T16:08:38.194017624Z"
+  }
+}
+```
+
+### All evidence
+
+Get all evidence
+
+```bash
+/cosmos/evidence/v1beta1/evidence
+```
+
+Example:
+
+```bash
+curl -X GET "http://localhost:1317/cosmos/evidence/v1beta1/evidence"
+```
+Example Output:
+
+```bash
+{
+  "evidence": [
+    {
+      "consensus_address": "cosmosvalcons1ntk8eualewuprz0gamh8hnvcem2nrcdsgz563h",
+      "height": "11",
+      "power": "100",
+      "time": "2021-10-20T16:08:38.194017624Z"
+    }
+  ],
+  "pagination": {
+    "total": "1"
+  }
+}
+```
+
+## gRPC
+
+A user can query the `evidence` module using gRPC endpoints.
+
+### Evidence
+
+Get evidence by hash
+
+```bash
+cosmos.evidence.v1beta1.Query/Evidence
+```
+
+Example:
+
+```bash
+grpcurl -plaintext -d '{"evidence_hash":"DF0C23E8634E480F84B9D5674A7CDC9816466DEC28A3358F73260F68D28D7660"}' localhost:9090 cosmos.evidence.v1beta1.Query/Evidence
+```
+
+Example Output:
+
+```bash
+{
+  "evidence": {
+    "consensus_address": "cosmosvalcons1ntk8eualewuprz0gamh8hnvcem2nrcdsgz563h",
+    "height": "11",
+    "power": "100",
+    "time": "2021-10-20T16:08:38.194017624Z"
+  }
+}
+```
+
+### All evidence
+
+Get all evidence
+
+```bash
+cosmos.evidence.v1beta1.Query/AllEvidence
+```
+
+Example:
+
+```bash
+grpcurl -plaintext localhost:9090 cosmos.evidence.v1beta1.Query/AllEvidence
+```
+Example Output:
+
+```bash
+{
+  "evidence": [
+    {
+      "consensus_address": "cosmosvalcons1ntk8eualewuprz0gamh8hnvcem2nrcdsgz563h",
+      "height": "11",
+      "power": "100",
+      "time": "2021-10-20T16:08:38.194017624Z"
+    }
+  ],
+  "pagination": {
+    "total": "1"
+  }
+}
+```