I wonder why you set them not to compile in the first place, but fortunately, reversing that decision is easy. Go to the contents pane of Compile and ⌥ click on a checkbox in the include column.
I wonder why you set them not to compile in the first place, but fortunately, reversing that decision is easy. Go to the contents pane of Compile and ⌥ click on a checkbox in the include column.