improve test readme (#582)

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### Platforms affected


### What does this PR do?


### What testing has been done on this change?


### Checklist
- [ ] [Reported an issue](http://cordova.apache.org/contribute/issues.html) in the JIRA database
- [ ] Commit message follows the format: "CB-3232: (android) Fix bug with resolving file paths", where CB-xxxx is the JIRA ID & "android" is the platform affected.
- [ ] Added automated test coverage as appropriate for this change.

test/README.md

@@ -22,7 +22,7 @@
 # Cordova Android Test Project
 
 The project in this directory is an Android Test project that enables those
-interested in further developing cordova-android to validate their changes.
+interested in further developing `cordova-android` to validate their changes.
 
 ## Requirements
 
@@ -33,7 +33,7 @@ writing) at least version 3.3 or newer.
 ## Getting Started
 
 You can run this test project from both the command line as well as from
-Android Studio.
+Android Studio:
 
 ### Command Line
 
@@ -50,8 +50,10 @@ end-to-end, or instrumented, tests. Unit tests do not require any particular
 environment to run in, but the instrumented tests, however, require a connected
 Android device or emulator to run in.
 
-To run the unit tests, run: `gradlew test`.
-To run the instrumented tests, run: `gradlew connectedAndroidTest`.
+- To run the unit tests, run: `gradlew test`.
+- To run the instrumented tests, run: `gradlew connectedAndroidTest`.
+
+To make sure all tests are run, add the `--rerun-tasks` parameter.
 
 ### Android Studio