message: fix for ampersand in image URL (Issue
diff: @@ -1108,7 +1108,7 @@ var PptxGenJS = function(){
  strSlideXml += '<p:pic>';
  strSlideXml += ' <p:nvPicPr>'
  - strSlideXml += ' <p:cNvPr id="'+ (idx + 2) +'" name="Object '+ (idx + 1) +'" descr="'+ slideItemObj.image +'">';
  + strSlideXml += ' <p:cNvPr id="'+ (idx + 2) +'" name="Object '+ (idx + 1) +'" descr="'+ encodeXmlEntities(slideItemObj.image) +'">';
  if ( slideItemObj.hyperlink && slideItemObj.hyperlink.url ) strSlideXml += '<a:hlinkClick r:id="rId'+ slideItemObj.hyperlink.rId +'" tooltip="'+ (slideItemObj.hyperlink.tooltip ? encodeXmlEntities(slideItemObj.hyperlink.tooltip) : '') +'" />';
  if ( slideItemObj.hyperlink && slideItemObj.hyperlink.slide ) strSlideXml += '<a:hlinkClick r:id="rId'+ slideItemObj.hyperlink.rId +'" tooltip="'+ (slideItemObj.hyperlink.tooltip ? encodeXmlEntities(slideItemObj.hyperlink.tooltip) : '') +'" action="ppaction://hlinksldjump" />';
  strSlideXml += ' </p:cNvPr>';
  