Fix NPE if log message is null (Fixes #3)

pom.xml

@@ -8,7 +8,7 @@
     <packaging>jar</packaging>
 
     <name>ColorConsole</name>
-    <version>2.2</version>
+    <version>2.3</version>
     <inceptionYear>2016</inceptionYear>
     <url>http://dev.bukkit.org/bukkit-plugins/colorconsole/</url>
     <description>

src/main/java/com/github/games647/colorconsole/common/CommonFormatter.java

@@ -48,6 +48,10 @@ public class CommonFormatter {
     }
 
     public boolean shouldIgnore(String message) {
+        if (message == null) {
+            return false;
+        }
+
         for (String ignore : ignoreMessages) {
             if (message.contains(ignore)) {
                 return true;