Added babl.rb package. (#2581)

packages/babl.rb

+require 'package'
+
+class Babl < Package
+  description 'babl is a dynamic, any to any, pixel format translation library.'
+  homepage 'http://gegl.org/babl/'
+  version '0.1.56'
+  source_url 'https://download.gimp.org/pub/babl/0.1/babl-0.1.56.tar.bz2'
+  source_sha256 '8ad26ca717ec3c74e261f454dd6bb316333a39fd1f87db4ac44706a860dc4d28'
+
+
+  def self.build
+    system "./configure", "--prefix=#{CREW_PREFIX}", "--libdir=#{CREW_LIB_PREFIX}"
+    system "make"
+  end
+
+  def self.install
+    system "make", "DESTDIR=#{CREW_DEST_DIR}", "install"
+  end
+
+  def self.check
+    system "make", "check"
+  end
+end