doc: add link to udev hwdb in rel motion normalization doc

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
doc: move the wiki's scrolling documentation to here

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
doc: move the wiki's tapping documentation to here

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
doc: move the wiki's palm detection docs to here

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>