Added new SConscript-based build system; not yet done porting

SConstruct

@@ -0,0 +1,30 @@
+
+env = Environment()
+
+env.MergeFlags("-std=gnu99 -Wall -Wextra -Werror -Wno-unused-parameter -Wno-attributes")
+env['MODE'] = 'shared'
+
+AddOption("--variant",
+          dest="variant",
+          nargs=1, type="choice",
+          choices=["debug", "opt"],
+          default="debug",
+          action="store",
+          help="Build variant (debug or opt)")
+
+env['BUILDDIR'] = 'build/$VARIANT'
+
+dbg = env.Clone(VARIANT='debug')
+dbg.Append(CCFLAGS=['-g'])
+
+opt = env.Clone(VARIANT='opt')
+opt.Append(CCFLAGS="-O3")
+
+if GetOption("variant") == 'debug':
+    env = dbg
+else:
+    env = opt
+Export('env')
+
+env.SConscript(["src/SConscript"], variant_dir='build/$VARIANT/src')
+env.SConscript(["examples/SConscript"], variant_dir='build/$VARIANT/examples')