Upload files option added

Clicking on new 'Upload File(s)' option triggers a function to click the
file input button. onChange of this value, the submit function is called
to post the form
2 new functions to select & submit uploaded files

Select function sets uploadedDir hidden form field and clicks the file
input button for user. Submit function is automatically triggered when
files value changes, which then shows the loading screen and submits the
form. preventDefault is also needed here.
Upload files function added

This function will get uploaded file details for each file uploaded and
when uploaded, move the file to the user selected folder. Also shows
error message if there is an issue. Either way, when finished it will
clear the selectedFiles, file menu and hide the loading mask to return
user to normal view.
Disallow traversing to parent dir