fix for #239, added underscore as valid model name construct

Author: fehguy

modules/swagger-core/src/main/scala/com/wordnik/swagger/converter/ModelPropertyParser.scala

@@ -129,7 +129,7 @@ class ModelPropertyParser(cls: Class[_]) (implicit properties: LinkedHashMap[Str
       if (!"void".equals(paramType) && null != paramType && !processedFields.contains(name)) {
         if(!excludedFieldTypes.contains(paramType)) {
           val items = {
-            val ComplexTypeMatcher = "([a-zA-Z]*)\\[([a-zA-Z\\.\\-0-9]*)\\].*".r
+            val ComplexTypeMatcher = "([a-zA-Z]*)\\[([a-zA-Z\\.\\-0-9_]*)\\].*".r
             paramType match {
               case ComplexTypeMatcher(containerType, basePart) => {
                 LOGGER.debug("containerType: " + containerType + ", basePart: " + basePart + ", simpleName: " + simpleName)