Removed Expected Exception from Test, because functionality of module UF:D:shell has changed.
UF:D:shell could now be null
Removed unused imports from UF:D:shell
Removed test TestFillAttribute because module UF:D:shell does not have fill method
Merge pull request #87 from papperwing/shellTest

Modified tests so them reflect current behaviour of modules for unix shell.
Removed unused imports from UF:D:shell.