Add documentation for preserveTestName

Author: tasha-urbancic

README.md

@@ -24,6 +24,7 @@ The [documentation website](https://ember-cli.github.io/ember-exam/) contains ex
     + [Split Test Parallelization](#split-test-parallelization)
   * [Test Load Balancing](#test-load-balancing)
       - [Test Failure Reproduction](#test-failure-reproduction)
+  * [Preserve Test Name](#preserve-test-name)
 - [Advanced Configuration](#advanced-configuration)
   * [Ember Try & CI Integration](#ember-try--ci-integration)
   * [Test Suite Segmentation](#test-suite-segmentation)
@@ -375,6 +376,33 @@ $ ember exam --replay-execution=test-execution-000000.json
 3. You must be using `qunit` version 2.8.0 or greater for this feature to work properly.
 4. This feature is not currently supported by Mocha.
 
+#### Preserve Test Name
+
+When using `--split` and/or `--load-balance` the output will look something like:
+
+```bash
+# ember exam --split=2 --partition=1 --parallel=3 --load-balance
+ok 1 Chrome 66.0 - Exam Partition 1 - browser Id 1 - some test
+ok 2 Chrome 66.0 - Exam Partition 1 - browser Id 2 - another test
+ok 3 Chrome 66.0 - Exam Partition 1 - browser Id 3 - some the other test
+```
+However, if you change the amount of parallelization, or randomize across partitions, the output will change for the same test, which may be an issue if you are tracking test insights over time. 
+
+```bash
+# ember exam --split=2 --partition=1 --parallel=2 --load-balance
+ok 1 Chrome 66.0 - Exam Partition 1 - browser Id 2 - some test
+ok 2 Chrome 66.0 - Exam Partition 1 - browser Id 1 - another test
+ok 3 Chrome 66.0 - Exam Partition 1 - browser Id 2 - some the other test
+```
+You can add `--preserve-test-name` to remove the dynamic segments of the output (partition and browser) to ensure the output test names are always the same.
+
+```bash
+# ember exam --split=2 --partition=1 --parallel=3 --load-balance --preserve-test-name
+ok 1 Chrome 66.0 - some test
+ok 2 Chrome 66.0 - another test
+ok 3 Chrome 66.0 - some the other test
+```
+
 ## Advanced Configuration
 
 Ember Exam does its best to allow you to run your test suite in a way that is effective for your individual needs. To that end, there are lots of advanced ways to configure your setup by integrating with other aspects of the Ember testing environment. The following sections will cover a few of the more common scenarios.

tests/dummy/app/router.js

@@ -15,6 +15,7 @@ Router.map(function () {
     this.route('split-parallel');
     this.route('filtering');
     this.route('load-balancing');
+    this.route('preserve-test-name');
 
     this.route('ember-try-and-ci');
     this.route('test-suite-segmentation');

tests/dummy/app/templates/docs.hbs

@@ -13,6 +13,7 @@
     {{nav.item "Split Test Parallelization" "docs.split-parallel"}}
     {{nav.item "Filtering" "docs.filtering"}}
     {{nav.item "Test Load Balancing" "docs.load-balancing"}}
+    {{nav.item "Preserve Test Name" "docs.preserve-test-name"}}
 
     {{nav.section "Advanced Configuration"}}
     {{nav.item "Ember Try & CI Integration" "docs.ember-try-and-ci"}}

tests/dummy/app/templates/docs/preserve-test-name.md

@@ -0,0 +1,26 @@
+# Preserve Test Name
+
+When using `--split` and/or `--load-balance` the output will look something like:
+
+```bash
+# ember exam --split=2 --partition=1 --parallel=3 --load-balance
+ok 1 Chrome 66.0 - Exam Partition 1 - browser Id 1 - some test
+ok 2 Chrome 66.0 - Exam Partition 1 - browser Id 2 - another test
+ok 3 Chrome 66.0 - Exam Partition 1 - browser Id 3 - some the other test
+```
+However, if you change the amount of parallelization, or randomize accross partitions, the output will change for the same test, which may be an issue if you are tracking test insights over time. 
+
+```bash
+# ember exam --split=2 --partition=1 --parallel=2 --load-balance
+ok 1 Chrome 66.0 - Exam Partition 1 - browser Id 2 - some test
+ok 2 Chrome 66.0 - Exam Partition 1 - browser Id 1 - another test
+ok 3 Chrome 66.0 - Exam Partition 1 - browser Id 2 - some the other test
+```
+You can add `--preserve-test-name` to remove the dynamic segments of the output (partition and browser) to ensure the output test names are always the same.
+
+```bash
+# ember exam --split=2 --partition=1 --parallel=3 --load-balance --preserve-test-name
+ok 1 Chrome 66.0 - some test
+ok 2 Chrome 66.0 - another test
+ok 3 Chrome 66.0 - some the other test
+```