Summary:
This diff renames `__reload__` procedure to be `mg.reload` accepting a
module name. The main CallCustomProcedure function is now split into
multiple parts, so that there's more control over finding a procedure,
type checking its arguments and finally checking the returned result
set.
Depends on D2572
Reviewers: mferencevic, ipaljak
Reviewed By: ipaljak
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2573