documentation - updated the text of the documentation according to http://bugzilla.fcdonders.nl/show_bug.cgi?id=2096


git-svn-id: svn+ssh://svn.fcdonders.nl/home/svnroot/fieldtrip/trunk@9800 0cf7c7f0-3615-4144-b4e6-68da3bce3cd0
Merge branch 'master' of github.com:fieldtrip/fieldtrip