Summary: SmallVector data structure introduction. This is the first step. In this revision are SmallVector implementation and tests. The second step will be swapping std::vector with SmallVector in the current codebase.
Reviewers: teon.banek, buda, ipaljak, mtomic
Reviewed By: teon.banek, ipaljak
Subscribers: ipaljak, pullbot
Differential Revision: https://phabricator.memgraph.io/D1730
