Set extractor encoding to UTF-8

When compiling the extractor on Windows, you get more than 100 errors with the message error: unmappable character for encoding Cp1252, especially in timeago-parser tasks. This commit fixes it by setting the encoding for all compileJava and compileTestJava tasks to UTF-8.

build.gradle

@@ -2,6 +2,9 @@ allprojects {
     apply plugin: 'java-library'
     apply plugin: 'maven'
 
+    compileJava.options.encoding = 'UTF-8'
+    compileTestJava.options.encoding = 'UTF-8'
+
     sourceCompatibility = 1.8
     targetCompatibility = 1.8