Bump version to 1.5.2

Author: damianlegawiec

lib/spree_multi_vendor/version.rb

@@ -10,7 +10,7 @@ def version
   module VERSION
     MAJOR = 1
     MINOR = 5
-    TINY  = 1
+    TINY  = 2
     PRE   = nil
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join('.')