Handle variadic arguments to logDebug

This lets us do fancier logging such as:
```
logDebug('debug', {}, 'foo', true);
```

Author: mattrobenolt

.jshintrc

@@ -4,6 +4,7 @@
     "browser": true,
     "predef": [
         "TraceKit",
-        "console"
+        "console",
+        "_slice"
     ]
 }

src/raven.js

@@ -850,9 +850,11 @@ function uuid4() {
     }
 }
 
-function logDebug(level, message) {
+function logDebug(level) {
     if (window.console && console[level] && Raven.debug) {
-        console[level](message);
+        // _slice is coming from vendor/TraceKit/tracekit.js
+        // so it's accessible globally
+        console[level].apply(console, _slice.call(arguments, 1));
     }
 }
 

test/raven.test.js

@@ -322,6 +322,13 @@ describe('globals', function() {
             logDebug(level, message);
             assert.isTrue(console[level].calledOnce);
         });
+
+        it('should handle variadic arguments', function() {
+            Raven.debug = true;
+            this.sinon.stub(console, level);
+            logDebug(level, message, {}, 'foo');
+            assert.isTrue(console[level].calledOnce);
+        });
     });
 
     describe('setAuthQueryString', function() {