BUG: fix df concat containing mix of localized and non-localized Timestamps
BUG: fix issue with concat of localized timestamps
TST: test concat of dataframes with non-None timezone columns

Created #12467 and added it in test comment
 xref to #12396 which is closed by #12403 
 ping!
 Hey Jeff, I've looked into the other failures a little but don't fully understand when/why the expected dims change.  It looks like merge (the tests that fail) always wants a 1d array and is failing because we are using atleast_2d on one of our inputs to make our (2-d, 1-d) input combo compatible.  Perhaps we should instead be making the 2-d into a 1-d?  Is this just playing wack-a-mole?
 a bit of a hack, but assure 2d-ness only when we are axis=1 concat.

```
diff --git a/pandas/tseries/common.py b/pandas/tseries/common.py
index f32e9b9..11a5fdc 100644
--- a/pandas/tseries/common.py
+++ b/pandas/tseries/common.py
@@ -260,8 +260,7 @@ def _concat_compat(to_concat, axis=0, typs=None):
         # if dtype is of datetimetz or timezone
         if x.dtype.kind == _NS_DTYPE.kind:
             if getattr(x, 'tz', None) is not None:
-                x = x.asobject
-                x = np.atleast_2d(x)
+                x = x.asobject.values
             else:
                 shape = x.shape
                 x = tslib.ints_to_pydatetime(x.view(np.int64).ravel())
@@ -272,6 +271,8 @@ def _concat_compat(to_concat, axis=0, typs=None):
             x = tslib.ints_to_pytimedelta(x.view(np.int64).ravel())
             x = x.reshape(shape)

+        if axis == 1:
+            x = np.atleast_2d(x)
         return x

     if typs is None:
```
 That passes the tests that were failing. Unfortunately, can't push from work.  Will make that change this evening.
 @tsdlovell np.
 travis is failing on OSX and py3.5 at the same points

> ## ERROR: test_range_slice_day (pandas.tseries.tests.test_period.TestPeriodIndex)
> 
> Traceback (most recent call last):
>   File "/Users/travis/build/pydata/pandas/pandas/tseries/tests/test_period.py", line 2619, in test_range_slice_day
>     idx[v:]
>   File "/Users/travis/build/pydata/pandas/pandas/tseries/base.py", line 176, in **getitem**
>     result = getitem(key)
> 
> # IndexError: failed to coerce slice entry of type str to integer
> 
> ## ERROR: test_range_slice_seconds (pandas.tseries.tests.test_period.TestPeriodIndex)
> 
> Traceback (most recent call last):
>   File "/Users/travis/build/pydata/pandas/pandas/tseries/tests/test_period.py", line 2676, in test_range_slice_seconds
>     idx[v:]
>   File "/Users/travis/build/pydata/pandas/pandas/tseries/base.py", line 176, in **getitem**
>     result = getitem(key)
> IndexError: failed to coerce slice entry of type str to integer

Was working in the env I created a bit ago, but fails in an env I just created, so maybe something to do with change in dependencies.   Will look into it.
 numpy 1.11 was just updated fully in conda
I am about to push the fixes for this
 rebase and should be good to go
 @tsdlovell thank you sir!
