Add unit test for function with variable number of arguments
Add unit test for function with variable number of arguments

xinghun92/rusqlite,mikelodder7/rusqlcipher,xinghun92/rusqlite,gwenn/rusqlite,jgallagher/rusqlite,gwenn/rusqlite,mikelodder7/rusqlcipher,mikelodder7/rusqlcipher,gwenn/rusqlite,xinghun92/rusqlite,jgallagher/rusqlite,jgallagher/rusqlite