add mavenCentral to repositories

build.gradle

@@ -1,7 +1,7 @@
 buildscript {
     repositories {
         google()
-        jcenter()
+        mavenCentral()
     }
 
     dependencies {
@@ -14,6 +14,8 @@ buildscript {
 allprojects {
     repositories {
         google()
+        mavenCentral()
+        // needed for some legacy libs that aren't available on mavenCentral
         jcenter()
     }
 }