Deprecate get and set methods on HasTraits

[sjagoe]

@rkern Here is a new PR replacing #124. It also marks get and set as deprecated with tests to assert that they log the deprecation warning.

[coveralls]

Coverage increased (+0.19%) when pulling a222f20 on sjagoe:remove-get-set into 83eb368 on enthought:master.

[mdickinson]

@sjagoe: RTM?

[mdickinson]

I get one failure on this branch:

======================================================================
FAIL: test_trait_set_deprecated (traits.tests.test_trait_get_set.TestTraitGet)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/mdickinson/Enthought/Source/meta-geophysics/meta-ETS/traits/traits/tests/test_trait_get_set.py", line 80, in test_trait_set_deprecated
    self.assertEqual(len(handler.records), 1)
AssertionError: 0 != 1

[mdickinson]

@sjagoe: How on earth did you bamboozle Travis into passing?!

[mdickinson]

Okay, so the issue is that this test will only pass if HasTraits.set has not been called previously. And some recent change to TraitsUI introduced a HasTraits.set operation, which is triggered by a Traits import. Below is the (partial) stack trace leading to that operation.

I think the deprecation part of this PR should be revisited after dealing with PR #196.

  File "traits/tests/test_trait_get_set.py", line 21, in <module>
    from traits.testing.unittest_tools import unittest
  File "traits/testing/unittest_tools.py", line 19, in <module>
    from traits.api import (Any, Event, HasStrictTraits, Instance, Int, List,
  File "traits/api.py", line 107, in <module>
    from traitsui import view_elements
  File "/Users/mdickinson/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/traitsui/view_elements.py", line 37, in <module>
    from .view_element import ViewElement
  File "/Users/mdickinson/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/traitsui/view_element.py", line 34, in <module>
    from .ui_traits import (ATheme, AnObject, DockStyle, EditorStyle, ExportType,
  File "/Users/mdickinson/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/traitsui/ui_traits.py", line 371, in <module>
    class HasMargin ( TraitType ):
  File "/Users/mdickinson/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/traitsui/ui_traits.py", line 380, in HasMargin
    default_value = Margin( 0 )
  File "/Users/mdickinson/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/traitsui/ui_traits.py", line 327, in __init__
    self.set( left = left, right = right, top = top, bottom = bottom )

[mdickinson]

#220 changes the deprecated decorator and adds a new assertDeprecated assertion to UnittestTools. If that gets merged, testing the deprecation in this PR should be easier.

[sjagoe]

Updated with tests for deprecation warnings from #220.

[mdickinson]

Thanks. We still need a CHANGES.txt entry, but apart from that this LGTM.

[coveralls]

Coverage increased (+0.05%) when pulling 9bc1db1 on sjagoe:remove-get-set into 0c301d2 on enthought:master.

[coveralls]

Coverage increased (+0.06%) when pulling 3f8cd30 on sjagoe:remove-get-set into 0c301d2 on enthought:master.

[mdickinson]

Merging. Thanks!