astyle run [ci skip]
Add a new test for OpenFile function from windows.cfg.
It is here as a reminder for a TODO. When used with OF_EXIST flag, the function OpenFile doesn't return a handle and thus, doesn't leak any resource.
As cppcheck doesn't support such feature yet, it's added a TODO not to be forgotten for later fix when cppcheck supports this.

Also added a naive check, just to ensure the OpenFile check doesn't get broken when adding support for OF_EXIST.
htmlreport: make link to index page ("Defect list") fixed on the screen so we can always access it regardless of how low we scrolled.
htmlreport: remove redundant <style> tags, make html output readable.
htmlreport: splitup HTML_HEAD where we want to insert the list of errors.
htmlreport: show index of errors of current page under Defect List link.
Preprocessor: set error flag when unhandled characters are found so checking can bailout
htmlreport: make content div overflow the menu properly when scrolling horizontally.
Merge pull request #330 from matthiaskrgr/htmlreport_2

Htmlreport: minor cleanup, write index of errors (with links) under "Defect list" in menu for each page
Merge pull request #329 from HeisSpiter/master

Add a new test for OpenFile function from windows.cfg.
htmlreport: print filename in file page heading.