formats.txt: Add info about WOFF and WOFF2.

docs/formats.txt

@@ -79,8 +79,7 @@ which isn't supported yet please send a mail too.
 
   SFNT    PS      TYPE_1  ---        type1    Type 1 GX Font Format
                                               (for the Mac) [3]
-  SFNT    PS      TYPE_1  CID        cid      5180.sfnt.pdf (for the Mac)
-                                              [3]
+  SFNT    PS      TYPE_1  CID        cid      5180.sfnt.pdf (for the Mac) [3]
   SFNT    PS      CFF     ---        cff      OT spec, 5176.CFF.pdf
                                               (`OTTO' format)
   SFNT    PS      CFF     CID        cff      OT spec, 5176.CFF.pdf
@@ -97,6 +96,12 @@ which isn't supported yet please send a mail too.
                                               (`?var' + `?VAR' tables)
 
 
+  WOFF    ---     ---     ---        cff,     Compressed SFNT, ver. 1.0 [6]
+                                     truetype
+  WOFF2   ---     ---     ---        cff,     Compressed SFNT, ver. 2.0 [6]
+                                     truetype
+
+
   ---     PS      TYPE_1  ---        type1    T1_SPEC.pdf
                                               (PFA, Type 1 font resource)
   PFB     PS      TYPE_1  ---        type1    T1_SPEC.pdf,
@@ -185,10 +190,14 @@ which isn't supported yet please send a mail too.
 
       https://fontforge.github.io/pcf-format.html
 
-[5] This is from MS Windows 3; see Microsoft's Knowledge Base article at
+[5] This is from MS Windows 3;  see Microsoft's Knowledge Base article
+    at
 
       https://support.microsoft.com/kb/65123
 
+[6] Supported  font  formats  are   TrueType  and  OpenType  fonts  as
+    defined in the OpenType specification 1.6 and newer.
+
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