libspatialite: Add --devel build

Now tracking the 4.0 release candidates.

Formula/libspatialite.rb

@@ -5,7 +5,13 @@ class Libspatialite < Formula
   url 'http://www.gaia-gis.it/gaia-sins/libspatialite-sources/libspatialite-3.0.1.tar.gz'
   sha1 'a88c763302aabc3b74d44a88f969c8475f0c0d10'
 
+  devel do
+    url 'http://www.gaia-gis.it/gaia-sins/libspatialite-4.0.0-RC1.tar.gz'
+    sha1 'a8fdbf76a4dc8a3388b49156dad99a3a788dc9b9'
+  end
+
   option 'without-freexl', 'Build without support for reading Excel files'
+  option 'with-lwgeom', 'Enable additional sanitization/segmentation routines provided by PostGIS 2.0+. (--devel builds only)'
 
   depends_on 'proj'
   depends_on 'geos'
@@ -15,6 +21,7 @@ class Libspatialite < Formula
   depends_on 'sqlite'
 
   depends_on 'freexl' unless build.include? 'without-freexl'
+  depends_on 'postgis' if build.include? 'with-lwgeom' and build.devel?
 
   def install
     # Ensure Homebrew's libsqlite is found before the system version.
@@ -26,6 +33,7 @@ class Libspatialite < Formula
       --with-sysroot=#{HOMEBREW_PREFIX}
     ]
     args << '--enable-freexl=no' if build.include? 'without-freexl'
+    args << '--enable-lwgeom' if build.include? 'with-lwgeom' and build.devel?
 
     system './configure', *args
     system "make install"