Updated the bins_dir to default to pg_bin #37935

The config looking for initdb wasn't consistent with documentation so this updates that. It might be best to add a default but I need to look into the code a bit more first.

salt/modules/postgres.py

@@ -26,6 +26,9 @@ Module to provide Postgres compatibility to salt.
     of the postgres bin's path to the relevant minion for this module::
 
         postgres.pg_bin: '/usr/pgsql-9.5/bin/'
+
+:note: Older versions of Salt had a bug where postgres.bins_dir was used
+    instead of postgres.pg_bin. You should upgrade this as soon as possible.
 '''
 
 # This pylint error is popping up where there are no colons?
@@ -112,7 +115,7 @@ def __virtual__():
     '''
     Only load this module if the psql and initdb bin exist
     '''
-    utils = ['psql', 'initdb']
+    utils = ['psql']
     if not HAS_CSV:
         return False
     for util in utils:
@@ -128,7 +131,15 @@ def _find_pg_binary(util):
 
     Helper function to locate various psql related binaries
     '''
-    pg_bin_dir = __salt__['config.option']('postgres.bins_dir')
+    pg_bin_dir = __salt__['config.option']('postgres.pg_bin')
+
+    if not pg_bin_dir:  # Fallback to incorrectly-documented setting
+        pg_bin_dir = __salt__['config.option']('postgres.bins_dir')
+        if pg_bin_dir:
+            log.warning(
+                'Using postgres.bins_dir is not supported. '
+                'Replace this with postgres.pg_bin')
+
     util_bin = salt.utils.which(util)
     if not util_bin:
         if pg_bin_dir: