Smoke test now uses portable file path

Added a sanity check to ensure smoke.sh is run from the correct folder
and use a relative path to the mona image so it works on any system.

.gitignore

@@ -4,4 +4,5 @@ build
 node_modules
 npm-debug.log
 out*.jpg
+out*.png
 examples/*.avi

smoke/smoke.sh

@@ -1,4 +1,10 @@
 #!/bin/bash
+
+if [ ! -f smoke/smoketest.js ]; then
+	echo "Please run smoke test from the top-level folder of the repository." >&2
+	exit 1
+fi
+
 node-gyp build && echo '-- Compiled OK -- 
 
 ' && node  smoke/smoketest.js && echo '-- Smoke Done, running tests --

smoke/smoketest.js

@@ -20,7 +20,7 @@ cv.readImage("/Users/peterbraden/Downloads/orl_faces/s6/10.pgm", function(e, im)
 
 
 */
-cv.readImage("/Users/peterbraden/Desktop/repos/node-opencv/examples/mona.png", function(e, mat){
+cv.readImage("examples/mona.png", function(e, mat){
   var th = mat.threshold(200, 200, "Threshold to Zero Inverted");
   th.save('out.png')