Improved error message and added inline troubleshooting tips. Closes #…

…3523

lib/hooks/grunt/index.js

@@ -200,7 +200,10 @@ module.exports = function(sails) {
 
         } // </console message contains "Fatal error">
 
-        // Handle fatal Grunt errors by killing Sails process as well
+        // Handle fatal Grunt errors by killing Sails process as well:
+        ////////////////////////////////////////////////////////////////////
+        //
+        // "Aborted due to warnings"
         else if (consoleMsg.match(/Aborted due to warnings/)) {
           sails.log.error('** Grunt :: An error occurred. **');
           // sails.log.warn(trimmedStackTrace);
@@ -209,12 +212,28 @@ module.exports = function(sails) {
           return;
         } // </console message contains "Aborted due to warnings">
 
+        // "Warning: EMFILE"
+        else if (consoleMsg.match(/Warning: EMFILE/)){
+          sails.log.error('** Grunt :: An EMFILE error occurred. **');
+          sails.log.error(
+            'Usually this means there are too many files open as per your system settings.\n'+
+            'If you are developing on one of the many unix-based operating systems that has\n'+
+            'the `ulimit` command, then you might try running: `ulimit -n 1024`.  For more tips,\n'+
+            'see https://github.com/balderdashy/sails/issues/3523#issuecomment-175922746.\n'+
+            '(command[⌘]+double-click to open links in the terminal)'
+          );
+          Err.fatal.__GruntAborted__(trimmedConsoleMsg, trimmedStackTrace);
+          return;
+        } // </console message contains "Warning: EMFILE">
+
+        // "ParseError"
         else if (consoleMsg.match(/ParseError/)) {
           sails.log.warn('** Grunt :: Parse Warning **');
           sails.log.warn(trimmedStackTrace);
         } // </console message contains "ParseError">
 
         // Only display console message if it has content besides whitespace
+        //////////////////////////////////////////////////////////////////
         else if (!consoleMsg.match(/^\s*$/)) {
           sails.log.verbose('Grunt :: ' + trimmedConsoleMsg);
         } // </console message has content which is not whitespace>