LL-367 LL-306 LL-357
* reducing amount of evernote api calls for getting tags
* created separate handles for dealing with both evernote note and resource contents and respective thumbnail generation
* added calls entityFilesGet and entityFileAdd
* replaced call entityThumbsRemove by calling entityRemove
* added file parameter to SSEntityDescA for call entityDescGet to have corresponding file returned if available
* finally replacing SSTagLabel.isTagLabel with private method getTagLabel to have special characters replaced upon creation instead of throwing exception in case an invalid tag label occurs
* changed uEsRemove to use entityRemove as well (foreign keys have been created for ues table as well)
* new table files to represent the mapping between entities and files containing the content of an entity
* new file extension pptx for new mime type applicationMspowerpoint2007
* writePDFFromXHTML has to be synchronized to avoid threading problems with ITextRenderer
* creating files from evernote note content and evernote resource content and thumbnails for files where possible depending on respective file extensions
* cleaning files and thumbnails physically on disk too when import for evernote account happens
* removing files, thumbnails and user event ids via entity table now when import for evernote account happens