duplicate loading

[WojciechNowicki]

I added to _showLoading: this.$element.find('.loading').remove();
because I saw problem with duplicate loading element. eg when refresh grid few times

 _showLoading: function() {
        if (this._settings.showLoadingOverlay) {
            this.$element.find('.loading').remove();
            this._loadingOverlay = $(this._settings.templates.loadingOverlayTemplate());
            this._sizeLoadingOverlay();
            this.$element.prepend(this._loadingOverlay);
        }
    },

[JamesRandall]

Thank you - I'll replicate the problem shortly and include your fix. Thanks!