Allows external access to functions

[joshuasiler]

I needed to be able to call:

// programmatically initiate preview
$("#myTextArea").markItUpExec('preview');

// initiate a preview update
$("#myTextArea").markItUpExec('refreshPreview');

[joshuasiler]

For more context on this, I found the built in previewAutoRefresh to be unreliable, so I wrote an updated one. You might want to consider incorporating this pattern.

refreshLocked = false

var updateTextilePreview = function() { 
    if(!refreshLocked)
    {
        refreshLocked = true;
        $("#job-desc-spinner").show();
        setTimeout(function() {
            refreshLocked = false;
            $("#job-description").markItUpExec('refreshPreview');
            $("#job-desc-spinner").hide();
        }, 5000);
    }
}

$(document).ready(function() {
                $("#job-description").markItUp(mySettings);
                // put up preview window
                $("#job-description").markItUpExec('preview');
                // markItUp autopreview refresh not reliable, so we implement our own
                $("#job-description").bind('change keyup paste', updateTextilePreview);
           });