License grant

Problem: lack of out-of-bound memory checks in tests

Solution: add a CI build run with GCC's Address Sanitizer enabled.
This compiler flag will make the unit test programs abort if it
detects errors such as out-of-bound memory access or use-after-free.

Problem: insufficient error handling relative to zap_connect.

Problem: assert used for ZAP error handling aborts process.

Problem: No relicense file for jemc contributions.

Solution: Add relicense file.

Relicense grant for chrisstaite

RELICENSE: Aaron Linville grant

Improve oom handling

Solution: Use the appropriate assertion macro.

Solution: Do it unconditionally.

Solution: Pass (std::nothrow) as done in all other places.

RELICENSE: Ian Barber grant

Problem: need to relicense libzmq

RELICENSE: Nick Guiffrida grant

RELICENSE: Björn Töpel / bjoto

Problem: insufficient use of const complicates calling.

Problem: typo in comment.

Added relicense permit