MooseSharedPointer should use .get()
(refs #4024)
Comparisons on shared pointers need .get() called

Refs #4042
Merge pull request #9 from andrsd/null-shared

Comparisons on shared pointers need .get() called
Merge pull request #4127 from aeslaughter/null-shared

MooseSharedPointer should use .get()
Merge commit 'e64e056cf358ea0960bace6df3b371e75456d4cc'