[17.01] Fix order of PATH when doing hacky Conda activating.

Thanks to @yhoogstrate's comment here fe2a1d8#commitcomment-20900607.

lib/galaxy/tools/deps/resolvers/conda.py

@@ -325,7 +325,7 @@ def shell_commands(self, requirement):
             # On explicit testing the only such requirement I am aware of is samtools - and it seems to work
             # fine with just appending the PATH as done below. Other tools may require additional
             # variables in the future.
-            return """export PATH=$PATH:'%s/bin' """ % (
+            return """export PATH='%s/bin':$PATH """ % (
                 self.environment_path,
             )
         else: