Relax return-count check

Increased the number of allowed return statements to three. Restricting
the number of return statements to two resulted in code that was less
easier to read than code with more return statements.

Author: cboehme

quality_assurance/checkstyle_rules.xml

@@ -5,7 +5,7 @@
     This configuration file was written by the eclipse-cs plugin configuration editor
 -->
 <!--
-    Checkstyle-Configuration: Metafacture
+    Checkstyle-Configuration: Culturegraph
     Description: none
 -->
 <module name="Checker">
@@ -77,7 +77,9 @@
     <module name="RedundantThrows">
       <property name="suppressLoadErrors" value="true"/>
     </module>
-    <module name="ReturnCount"/>
+    <module name="ReturnCount">
+      <property name="max" value="3"/>
+    </module>
     <module name="SimplifyBooleanExpression"/>
     <module name="SimplifyBooleanReturn"/>
     <module name="StringLiteralEquality"/>
@@ -112,7 +114,7 @@
     <module name="JavadocType"/>
   </module>
   <module name="StrictDuplicateCode">
-  	<property name="fileExtensions" value="java"/>
+    <property name="fileExtensions" value="java"/>
   </module>
   <module name="Header">
     <property name="headerFile" value="${basedir}/quality_assurance/java-header.txt"/>