This commit enhances the MSB4064 error with additional information and
details such as:
 - assembly identity - it's full name containing the token ID, version
   and name.

The enhanced MSB4064 error message has previously been implemented
without assembly location. It has been added by this commit.
Note that assembly parameter used for the error message has been
replaced with loadedAssembly parameter, due to having the null name
property.

It turns out, that when executing the tests, the LoadedAssembly is null
which breaks the run.
To avoid such situation, checking for null has been implemented, so in
case of no assembly loaded the type is checked and it's path and name is
returned to the user/developer.