Add gimp package

Add libheif and openexr dependencies

Add xdg_base dependency

Add pre-built binaries

packages/gimp.rb

+require 'package'
+
+class Gimp < Package
+  description 'GIMP is a cross-platform image editor available for GNU/Linux, OS X, Windows and more operating systems.'
+  homepage 'https://www.gimp.org/'
+  version '2.10.6'
+  source_url 'https://download.gimp.org/pub/gimp/v2.10/gimp-2.10.6.tar.bz2'
+  source_sha256 '4ec8071f828e918384cf7bc7d1219210467c84655123f802bc55a8bf2415101f'
+
+  binary_url ({
+    aarch64: 'https://dl.bintray.com/chromebrew/chromebrew/gimp-2.10.6-chromeos-armv7l.tar.xz',
+     armv7l: 'https://dl.bintray.com/chromebrew/chromebrew/gimp-2.10.6-chromeos-armv7l.tar.xz',
+       i686: 'https://dl.bintray.com/chromebrew/chromebrew/gimp-2.10.6-chromeos-i686.tar.xz',
+     x86_64: 'https://dl.bintray.com/chromebrew/chromebrew/gimp-2.10.6-chromeos-x86_64.tar.xz',
+  })
+  binary_sha256 ({
+    aarch64: 'f237f502445c1dbd8aa88c1e5bb2bd74efaf53bb20712edce62f30436b24253d',
+     armv7l: 'f237f502445c1dbd8aa88c1e5bb2bd74efaf53bb20712edce62f30436b24253d',
+       i686: '7edecd8e91873795fc234d2000f2ac03392f5ce6947492d36bc9df582d7dd015',
+     x86_64: '8d2400b5806a22e5afc39b1ec1571a7fdba416dded25a77baa7192c32e0c2c64',
+  })
+
+  depends_on 'ghostscript'
+  depends_on 'glib_networking'
+  depends_on 'pango'
+  depends_on 'libexif'
+  depends_on 'libgudev'
+  depends_on 'libheif'
+  depends_on 'libmng'
+  depends_on 'libtiff'
+  depends_on 'libwmf'
+  depends_on 'aalib'
+  depends_on 'mypaint_brushes'
+  depends_on 'openexr'
+  depends_on 'poppler_data'
+  depends_on 'pygtk'
+  depends_on 'shared_mime_info'
+  depends_on 'xdg_base'
+  depends_on 'sommelier'
+
+  def self.build
+    system './configure',
+           "--prefix=#{CREW_PREFIX}",
+           "--libdir=#{CREW_LIB_PREFIX}",
+           '--disable-maintainer-mode'
+    system 'make'
+  end
+
+  def self.install
+    system "make", "DESTDIR=#{CREW_DEST_DIR}", "install"
+  end
+end