Add unit testing

.idea/modules.xml

@@ -3,7 +3,7 @@
   <component name="ProjectModuleManager">
     <modules>
       <module fileurl="file://$PROJECT_DIR$/app/app.iml" filepath="$PROJECT_DIR$/app/app.iml" />
-      <module fileurl="file://$PROJECT_DIR$/tippy_1.1.3.iml" filepath="$PROJECT_DIR$/tippy_1.1.3.iml" />
+      <module fileurl="file://$PROJECT_DIR$/sst-tippytipper.iml" filepath="$PROJECT_DIR$/sst-tippytipper.iml" />
     </modules>
   </component>
 </project>
\ No newline at end of file

.idea/vcs.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file

app/build.gradle

@@ -24,4 +24,5 @@ android {
 
 dependencies {
     implementation files('libs/FlurryAgent.jar')
+    testImplementation 'junit:junit:4.12'
 }

app/src/test/java/net/mandaria/tippytipper/services/TipCalculatorServiceTest.java

+package net.mandaria.tippytipper.services;
+
+import org.junit.Test;
+
+import static junit.framework.Assert.assertTrue;
+import static junit.framework.Assert.fail;
+
+public class TipCalculatorServiceTest {
+
+    @Test
+    public void testShouldFail() {
+        TipCalculatorService t = new TipCalculatorService();
+        fail(":-(");
+    }
+}
\ No newline at end of file