Categorical: let unique only return used categories
BUG: Resample across multiple days

Fixes an issue where resampling over multiple days causes a ValueError
when a number of days between the normalized first and normalized last
days is not a multiple of the frequency.

Added test TestResample.test_resample_anchored_multiday

Closes #8683
BUG: Fixed font size (set it on both x and y axis). #8765
Merge pull request #8937 from JanSchulz/cat_unique2

Categorical: let unique only return used categories
BLD: run slow tests on new optional build 2.7_SLOW using current versions of everything
BLD: run graphics tests on 2.7_LOCALE using old matplotlib
preserve left frame order in left merge
TST: skip on < mpl 1.3.1 (GH8947)
Merge pull request #8941 from hkleynhans/fix/8683_resample_value_error

BUG: Resample across multiple days
Merge pull request #8949 from jreback/graphics

BLD/TST: skip mpl 1.2.1 tests (GH8947)
TST: Moved test functions to module level. #8023

TST: changed *args, **kwargs to fixed arguments. #8023

TST: Moved rest of the test functions to module level. #8023

TST: patch all module level assert functions to TestCase. #8023

CLN: Cleanup TestCase assert functions pathing #8023
Merge pull request #8940 from papaloizouc/8765_bug_fontsize_only_on_x_axis

BUG: Fixed font size (set it on both x and y axis). #8765
Merge pull request #8948 from behzadnouri/left-merge

BUG: preserve left frame order in left merge