Minor changes to display messages for examples

Fixed a bug with autodetecting input shape

Author: Ahmed Eldawy

src/operations/edu/umn/cs/spatialHadoop/CommandLineArguments.java

@@ -226,7 +226,7 @@ public Shape getShape(boolean autodetect) {
       }
     }
 
-    if (autodetect && shapeType.getLength() == 0) {
+    if (autodetect && shapeType.getLength() == 0 && getPath() != null) {
       // Shape type not found in parameters. Try to infer from a line in input
       // file
       Path in_file = getPath();

src/operations/edu/umn/cs/spatialHadoop/operations/Main.java

@@ -18,7 +18,7 @@ public static void main(String[] args) {
     try {
 
       pgd.addClass("rangequery", RangeQuery.class,
-          "Finds all objects in the query range given by rect:x1,y1,w,h");
+          "Finds all objects in the query range given by a rectangle");
 
       pgd.addClass("knn", KNN.class,
           "Finds the k nearest neighbor in a file to a point");