Compilation with libc++, as is default in Mac OSX Mavericks

Also merged with barche's branch.
@barche, you may want to review this before we send this upstream, as there are a few build problems with UFEM
see:
http://coolfluidsrv.vki.ac.be/cdash/index.php?project=coolfluid&date=2013-11-26&display=project&filtercount=4&showfilters=1&filtercombine=and&field1=buildname/string&compare1=61&value1=gcc4.4-Release-wdeconinck&field2=site/string&compare2=61&value2=RMA-mach-centos6.2&field3=buildstarttime/date&compare3=83&value3=2013-11-26T00:46:36%20CET&field4=buildstarttime/date&compare4=84&value4=2013-11-26T01:28:14%20CET&collapse=0

The build problems don't seem related to libc++, and perhaps you have fixed them in further commits in your branch