By default, NetBeans don't display hidden directories or files (starting with a dot[.]).
A regular expression handles directories or files discovery in NetBeans.
In order to modify this RegEx go to:
Tools -> Options -> Miscellaneous -> Files
and remove the part which exclude hidden files and directories
In my case my final result will be:
* Tested in NetBeans 7.4
For older versions you might want to check Hubert A. Klein Ikkink's article