swftools: rename internal Xpdf class

I don't really feel like taking the time to grok what is going on in
this formula, but reopening the Xpdf class like this causes problems if
the actual Xpdf class is loaded as well, so rename it.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Library/Formula/swftools.rb

@@ -1,6 +1,6 @@
 require 'formula'
 
-class Xpdf < Formula
+class XpdfTarball < Formula
   url 'ftp://ftp.foolabs.com/pub/xpdf/xpdf-3.03.tar.gz', :using  => :nounzip
   sha1 '499423e8a795e0efd76ca798239eb4d0d52fe248'
 end
@@ -31,7 +31,7 @@ def patches
   end
 
   def install
-    Xpdf.new.brew { (buildpath+'lib/pdf').install Dir['*'] } if build.include? "with-xpdf"
+    XpdfTarball.new.brew { (buildpath+'lib/pdf').install Dir['*'] } if build.include? "with-xpdf"
     system "./configure", "--prefix=#{prefix}"
     system "make"
     system "make install"