Update Qt Creator Manual according to the change log.

Other planned changes:

• Move detailed information about preferences and other buttons and fields from the manual into tooltips in the UI
• Improve descriptions of project wizard templates in the UI and remove them from the manual
• Improve tooltips/help for the locator in the UI and remove the filter information from the manual
• Update icons on the front page to use versions of the mode bar icons
• Improve plugin descriptions in the UI and add links to the plugin docs (Check that all plugins have places to link to. What to do with undocumented plugins?)
• Try to make the All Topics more visible for users who want a flat view of all sections in the manual for searching
• Improve the change log to contain sections that describe the new features instead of just a list of what changed