Mark a folder as ignore when building a package

Just a quick question of is there a way to mark a folder as ignored when exporting unity packages out. I have some sub folders that contain development stuff/exampled that dont need to go out etc. Currently everytime i need to update the package internally i have to go through and deselect all these folders (to stop the bloat of importing it into the new project).

Is there a way to say ignore folder X and Y during the exporting process

thanks

@reddevildragg -
I believe if you prefix any file or folder with dot .

that Unity will ignore it. In windows it is easiest to use the command line.

$> rename asset .asset

When I do this, the asset seems to be ignored by Unity