Document that olefile is required for FPX and MIC formats

Author: radarhere

docs/handbook/image-file-formats.rst

@@ -1296,6 +1296,8 @@ Pillow reads Kodak FlashPix files. In the current version, only the highest
 resolution image is read from the file, and the viewing transform is not taken
 into account.
 
+To enable FPX support, you must install olefile.
+
 .. note::
 
     To enable full FlashPix support, you need to build and install the IJG JPEG
@@ -1372,6 +1374,8 @@ the first sprite in the file is loaded. You can use :py:meth:`~PIL.Image.Image.s
 
 Note that there may be an embedded gamma of 2.2 in MIC files.
 
+To enable MIC support, you must install olefile.
+
 MPO
 ^^^