Rectified the names of the fixtrure classes.
Use AutoMockFixtureAttribute

This commit used AutoMockFixtureAttribute to customize a fixture
instance.
Update the StyleCop.MSBuild package

This commit updated the StyleCop.MSBuild package from v4.7.44.1 to
v4.7.45.0.
Clarified the class name.
Remove the obsolte attribute

This commit removed the obsolte attribute because if the attribute is
delcared, code analysis error will be occured.
Introduced CustomizationFixtureAttribute.
Treated SharedFixtureAttribute as obsolete.
Increment patch version number

This commit is to indicate that this patch version treated
SharedFixtureAttribute as obsolete.