petri net api 4.02

Closes Homebrew/homebrew#12140.

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

Formula/pnapi.rb

@@ -0,0 +1,20 @@
+require 'formula'
+
+class Pnapi < Formula
+  homepage 'http://service-technology.org/tools/petri_net_api'
+  url 'http://download.gna.org/service-tech/pnapi/pnapi-4.02.tar.gz'
+  sha1 'caa61aaa5886381e594f7eb57a75c1feb6960c3a'
+
+  depends_on "graphviz"
+
+  def install
+    system "./configure", "--prefix=#{prefix}"
+    system "make install"
+    # for some reason config.h is not installed by the Makefile
+    (include/'pnapi').install 'src/config.h'
+  end
+
+  def test
+    system "#{bin}/petri", "--help"
+  end
+end