Refactoring the SharedFixtureAttribute class

The commit improve code quaity with the refactoring(Extract Method).
Address correct test name

This commit addressed to be more appropriate test name.
Rearrange file and folder structure

Representing as UnitTest is more appropriate than seprating
AcceptanceTest and UnitTest.
Rename the parameter name to sut
Extract AutoDataTheoryCommandCustomizationTest

This commit extracted AutoDataTheoryCommandCustomizationTest from
AutoDataTheoryCommandTest.
Clarify the class name
Clarify the class names
Rearrange namespace and class names
Remove the TypeMembers class

The TypeMembers class is not necessary for unit testing.
Rename the test names
Introduce the Namespace property

This commit indroduced the property in the SharedFixtureAttribute class,
under which the fixture instance will be customized.
Rename the fixture classes
Move the SuppressMessage attribute

This attribute was moved from class level to assembly level.
Customize namespace level fixture

This is the new fixture customization on namespace level.
Improve slightly
Introduce the GetNamespace method
Resolve code analysis errors
Increment minor version(v1.1.0)

This indicates that the feature of shared fixture on namespace level is
new.