fontforge: add missing deps on png, jpeg, tiff

This commits adds recommended deps on png, jpeg, and libtiff
to FontForge, otherwise it will get various build errors and
runtime problems doing some font conversions. Lilypond for one
needs this. Also add an option to build in Gif support to round
out the image handling.

Closes Homebrew#16001.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

Library/Formula/fontforge.rb

@@ -10,17 +10,22 @@ class Fontforge < Formula
   env :std
 
   option 'without-python', 'Build without Python'
-  option 'with-x', 'Build with X'
-  option 'with-cairo', 'Build with Cairo'
-  option 'with-pango', 'Build with Pango'
-  option 'with-libspiro', 'Build with Spiro spline support'
+  option 'with-gif',       'Build with GIF support'
+  option 'with-x',         'Build with X'
+  option 'with-cairo',     'Build with Cairo'
+  option 'with-pango',     'Build with Pango'
+  option 'with-libspiro',  'Build with Spiro spline support'
 
   depends_on 'gettext'
   depends_on :xcode # Because: #include </Developer/Headers/FlatCarbon/Files.h>
 
-  depends_on :x11 if build.include? "with-x"
-  depends_on 'cairo' if build.include? "with-cairo"
-  depends_on 'pango' if build.include? "with-pango"
+  depends_on :libpng    => :recommended
+  depends_on 'jpeg'     => :recommended
+  depends_on 'libtiff'  => :recommended
+  depends_on :x11       if build.include? "with-x"
+  depends_on 'giflib'   if build.include? 'with-gif'
+  depends_on 'cairo'    if build.include? "with-cairo"
+  depends_on 'pango'    if build.include? "with-pango"
   depends_on 'libspiro' if build.include? "with-libspiro"
 
   fails_with :llvm do