Fix running from installation

sugar/Makefile.am

@@ -1,10 +1,11 @@
-SUBDIRS = chat browser shell
+SUBDIRS = chat browser p2p shell
 
 bin_SCRIPTS = sugar
 
 sugardir = $(pythondir)/sugar
 sugar_PYTHON =			\
 	__init__.py		\
-	__installed__.py
+	__installed__.py	\
+	env.py
 
-EXTRA_DIST = sugar
+EXTRA_DIST = sugar __uninstalled__.py

sugar/__installed__.py.in

@@ -1,2 +1,4 @@
+import os
+
 def internal_get_data_file(filename):
-	return "@prefix@/share/sugar"
+	return os.path.join('@prefix@/share/sugar', filename)