Complete / fix tutorial document

1. The end of page 75 and beginning of page 76 has highlighted text that needs to be completed
2. In the document, the figures for the modeling steps are not in the right order. Some figure references are missing as well.
3. The screenshots should be made bigger for better readability
4. Rename the provided ZigBeeDEMO.xml file to ZigBeeTutorial.xml so that users can identify it better
5. Update tutorial model / tutorial for the few elements that are not consistent. E.g. MainMemory is named DDR in model.
6. Write conclusion and link to the website for further info
7. Update the TTool logo