chore(tests2png): improve image generation script

Create img folder before running image generation script, and use verbose output when debugging.

For issue #697.

Author: staltz

package.json

@@ -29,7 +29,7 @@
     "cover": "istanbul cover -x \"*-spec.js index.js *-helper.js spec/helpers/*\" ./node_modules/jasmine/bin/jasmine.js && npm run cover_remapping",
     "cover_remapping": "remap-istanbul -i coverage/coverage.json -o coverage/coverage-remapped.json && remap-istanbul -i coverage/coverage.json -o coverage/coverage-remapped.lcov -t lcovonly && remap-istanbul -i coverage/coverage.json -o coverage/coverage-remapped -t html",
     "test": "jasmine",
-    "tests2png": "JASMINE_CONFIG_PATH=spec/support/tests2png.json jasmine",
+    "tests2png": "mkdirp img && JASMINE_CONFIG_PATH=spec/support/tests2png.json jasmine",
     "watch": "watch \"echo triggering build && npm run build_test && echo build completed\" src -d -u -w=15",
     "perf": "protractor protractor.conf.js",
     "perf_micro": "node ./perf/micro/index.js",
@@ -97,6 +97,7 @@
     "jasmine-core": "2.3.4",
     "lodash": "3.10.1",
     "markdown-doctest": "^0.2.0",
+    "mkdirp": "0.5.1",
     "platform": "1.3.0",
     "promise": "7.0.3",
     "protractor": "2.5.1",

spec/helpers/tests2png/painter.js

@@ -266,6 +266,6 @@ module.exports = function painter(inputStreams, operatorLabel, outputStream, fil
     if (err) {
       return console.error(arguments);
     }
-    //console.log(this.outname + ' created  :: ' + arguments[3]);
+    console.log(this.outname + ' created :: ' + arguments[3]);
   });
 };