Update README.md (#91)

* Update README.md

Modify the command that builds the memory footprint executable jar

* Update README.md

Author: lucianbc

play-validations/README.md

@@ -28,7 +28,7 @@ and variants.
 ## Building the tool
 
 ```bash
-./gradlew :memory-footprint:jar
+./gradlew :memory-footprint:executable-jar
 java -jar ./memory-footprint/build/libs/memory-footprint.jar --help
 ```
 

third_party/wff/README.md

@@ -19,7 +19,7 @@ specific watch face XML files.
 
 ```shell
 cd third_party/wff
-./gradlew :specification:validator:build
+./gradlew :specification:validator:executable-jar
 ```
 
 The resulting JAR file can then be found at: `specification/validator/build/libs/wff-validator.jar`
@@ -39,4 +39,4 @@ java -jar wff-validator.jar 4 ~/MyWatchface/res/raw/watchface.xml
 ```
 
 [xsd-files]: specification/documents/1
-[wff-features]: https://developer.android.com/training/wearables/wff/features
+[wff-features]: https://developer.android.com/training/wearables/wff/features