fix: Try to skip "license" URLs ending with image file name endings

The checker recognizes ALL URLs as license URLs, which is plainly wrong.
This is an experiment trying to improve the quality of detected URLs.

lib/exitProcessOrWarnIfNeeded.js

@@ -1,6 +1,6 @@
 const usageMessage = require('./usageMessage');
 
-module.exports = function exitProcessOrWarnIfNeeded ({ unknownArgs, parsedArgs, hasFailingArg }) {
+module.exports = function exitProcessOrWarnIfNeeded({ unknownArgs, parsedArgs, hasFailingArg }) {
     if (unknownArgs.length) {
         console.error(`license-checker-rseidelsohn@${require('../package.json').version}`, '\n');
         console.error(
@@ -35,4 +35,4 @@ module.exports = function exitProcessOrWarnIfNeeded ({ unknownArgs, parsedArgs,
             `Warning: The --${argName} argument takes semicolons as delimeters instead of commas (some license names can contain commas)`,
         );
     }
-}
+};

lib/getLicenseTitle.js

@@ -21,6 +21,7 @@ const CC0_1_0 =
     /The\s+person\s+who\s+associated\s+a\s+work\s+with\s+this\s+deed\s+has\s+dedicated\s+the\s+work\s+to\s+the\s+public\s+domain\s+by\s+waiving\s+all\s+of\s+his\s+or\s+her\s+rights\s+to\s+the\s+work\s+worldwide\s+under\s+copyright\s+law,\s+including\s+all\s+related\s+and\s+neighboring\s+rights,\s+to\s+the\s+extent\s+allowed\s+by\s+law.\s+You\s+can\s+copy,\s+modify,\s+distribute\s+and\s+perform\s+the\s+work,\s+even\s+for\s+commercial\s+purposes,\s+all\s+without\s+asking\s+permission./i; // jshint ignore:line
 const PUBLIC_DOMAIN = /[Pp]ublic[\-_ ]*[Dd]omain/;
 const IS_URL = /(https?:\/\/[-a-zA-Z0-9\/.]*)/;
+const DISCARD_URLS_ENDING_WITH = /(.svg|.gif|.png|.jpg|.jpeg)$/i;
 const IS_FILE_REFERENCE = /SEE LICENSE IN (.*)/i;
 const UNLICENSED = /UNLICENSED/i;
 
@@ -160,7 +161,11 @@ module.exports = function getLicenseTitle(str = 'undefined') {
     match = IS_URL.exec(str) || IS_FILE_REFERENCE.exec(str);
 
     if (match) {
-        return 'Custom: ' + match[1];
+        const matchedUrl = match[1];
+
+        if (!DISCARD_URLS_ENDING_WITH.test(matchedUrl)) {
+            return `Custom: ${matchedUrl}`;
+        }
     } else {
         return null;
     }