add exception text message
Merge branch 'master' of https://github.com/eranpeer/projects
Merge branch 'master' of https://github.com/eranpeer/projects
Merge branch 'master' of https://github.com/eranpeer/projects
Merge branch 'master' of https://github.com/eranpeer/projects
Throw IllegalArgumentException on Verify(...).Times(negative number)