fix width/height is scale NaN in img for export web page

[dwatow]

issue description

1. bitmapScale is undefined in xml file

       <Page xmlns:p="http://www.evolus.vn/Namespace/Pencil" id="b826fd07699d4543a02b200d8db96726" rasterized="/Users/chris/Desktop/pencil file/pages/detail.png">
           <Properties>
               <Property name="id">b826fd07699d4543a02b200d8db96726</Property>
               <Property name="fid">detail</Property>
               <Property name="name">detail</Property>
               <Property name="width">1382</Property>
               <Property name="height">671</Property>
               <Property name="pageFileName">page_b826fd07699d4543a02b200d8db96726.xml</Property>
               <Property name="zoom">1</Property>
               <Property name="backgroundColorRGBA">rgba(255, 255, 255, 0)</Property>
           </Properties>
           <Links>
               <Link target="02e736b4249f4f0b8f322fc9a45093e1" targetName="index" targetFid="index" x="151" y="338" w="92" h="25" />
           </Links>
       </Page>

2. width/undefined, height/undefined in xsl file

   
               <img src="{@rasterized}"
                   width="{p:Properties/p:Property[@name='width']/text() * p:Properties/p:Property[@name='bitmapScale']/text()}"
                   height="{p:Properties/p:Property[@name='height']/text() * p:Properties/p:Property[@name='bitmapScale']/text()}"
                   usemap="#map_{p:Properties/p:Property[@name='fid']/text()}"/>

3. img in export file

[dwatow]

@dgthanhan could you merge this?