fix man page typos (#194)

Author: r-ricci

jpegoptim.1

@@ -245,7 +245,7 @@ Strip JFIF markers from output file.
 .B --strip-jfxx
 Strip JFXX (JFIF Extensions) markers from output file.
 .TP 0.6i
-.B --strip-Adobe
+.B --strip-adobe
 Strip Adobe markers from output file.
 
 
@@ -265,13 +265,13 @@ Do not strip any ICC profiles from output file.
 .B --keep-xmp
 Do not strip any XMP profiles from output file.
 .TP 0.6i
-.B --strip-jfif
+.B --keep-jfif
 Do not strip any JFIF markers from output file.
 .TP 0.6i
-.B --strip-jfxx
+.B --keep-jfxx
 Do not strip any JFXX (JFIF Extensions) markers from output file.
 .TP 0.6i
-.B --keep-Adobe
+.B --keep-adobe
 Do not strip Adobe markers from output file.