Code called inside InModuleScope now retains file / line information

This causes failed tests to output the proper file and line from the tests.ps1 file, and also allows for setting breakpoints inside these blocks.

There are two other places that currently use Set-ScriptBlockScope and may lose similar information:  Mocks, and BeforeEach / AfterEach.  I'm not sure we can do much about the latter, but we can possibly add this same type of change to the Mocking code, if needed.
Reporting correct file name

For exceptions that are generated by something other than the Should command, test failure output now contains the file path and line number of whatever code produced the exception, instead of mixing the file path of the Tests.ps1 script and the line number from whatever file contained the error-producing code.

May revisit this to either change it to report the path / line number of the Tests.ps1 file (as failed Should assertions currently do), or output both sets of information.
Merge pull request #183 from dlwyatt/DebuggingInfoInModuleScope

Debugging info in module scope