Fix salt.states.selinux._refine_value()

This function was not properly handling True/False values, causing the
state not to work when one of these values is used. This makes the
example in the docstring fail.

Also cleaned up/simplified _refine_mode.

Fixes #5912.
Merge pull request #5917 from terminalmage/issue5912

Fix salt.states.selinux._refine_value()
Added note about multiline content when using file.managed.contents

Closes #5480
Merge pull request #5920 from whiteinge/doc-multiline-contents

Added note about multiline content when using file.managed.contents
fix indentation in states.selinux

************* Module salt.states.selinux
W0311: 33,0: Bad indentation. Found 12 spaces, expected 8
pillar.reclass_adapter: use "except X as Y" syntax
pillar/__init__.py: use modern "except X as Y" syntax
Merge pull request #5924 from cvrebert/patch-3

pillar/__init__.py: use modern "except X as Y" syntax
Merge pull request #5923 from cvrebert/patch-2

pillar.reclass_adapter: use "except X as Y" syntax
Merge pull request #5922 from cvrebert/patch-1

fix indentation in states.selinux
Fix oversights in addressing #5785

This commit catches up on changes introduced by
94d5c1797f1a3b6f5fa9fa4443b977715802a671. I overlooked some details and
this should now fix #5921 as well.

Closes: #5921
Signed-off-by: martin f. krafft <madduck@madduck.net>