enhancement - force conversion of sens and vol to double precision, added test script, removed warning_once (very slow) in the conversion, see http://bugzilla.fcdonders.nl/show_bug.cgi?id=2474


git-svn-id: svn+ssh://svn.fcdonders.nl/home/svnroot/fieldtrip/trunk@9208 0cf7c7f0-3615-4144-b4e6-68da3bce3cd0
automatically synchronized identical files to revision 9208

git-svn-id: svn+ssh://svn.fcdonders.nl/home/svnroot/fieldtrip/trunk@9209 0cf7c7f0-3615-4144-b4e6-68da3bce3cd0