setVersion.sh: new script which updates all version numbers in different documents.

 #3659 / Bootstrap default view: 'small' - fixed. By default '--viewport-size=1280x1024' will be set to wkhtml. This moves BS rendering 'xs' to 'md'.

Html2Pdf.php: Fake the current 'user-agent' and add it as '--custom-header ...' AND '--custom-header-propagation' option to the wkhtmltopdf call. Without, T3 will deny FE Group access. The --custom-header-propagation seems to be necessary.

Manual.rst: describe new urlParam parameter `_sip`
Html2Pdf.php: optional SIP encoding

Html2Pdf.php: Add SIP support wkhtmltopdf URLs. Move cookies for wkhtmltopdf from commandline arguments to filebased.

Session.php: introduced close(). This will unlock the current session. Take care on subsequent calls to reopen primary session again.

# Conflicts:
#	mockup/inputmodeswitcher.html

# Conflicts:
#	mockup/inputmodeswitcher.html