Merge pull request #2967 from ritzalam/improve-pdf2swf-conversion

bigbluebutton-web/grails-app/conf/bigbluebutton.properties

bigbluebutton-web/grails-app/conf/spring/doc-conversion.xml

.../java/org/bigbluebutton/presentation/ImageToSwfSlide.java

...rc/java/org/bigbluebutton/presentation/PageConverter.java

...rc/java/org/bigbluebutton/presentation/PdfToSwfSlide.java

...bluebutton/presentation/imp/ImageMagickPageConverter.java

...bigbluebutton/presentation/imp/Jpeg2SwfPageConverter.java

...gbluebutton/presentation/imp/Office2PdfPageConverter.java

...button/presentation/imp/OfficeToPdfConversionService.java

.../bigbluebutton/presentation/imp/Pdf2SwfPageConverter.java

...ton/presentation/imp/PdfPageToImageConversionService.java

...ton/presentation/imp/PdfToSwfSlidesGenerationService.java

.../bigbluebutton/presentation/imp/Png2SwfPageConverter.java