Improved tests and implementation of message_t

[sigiesec]

See individual commits

[coveralls]

Pull Request Test Coverage Report for Build 28

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• 4 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.9%) to 57.576%

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Files with Coverage Reduction	New Missed Lines	%
zmq.hpp	4	65.33%

Totals
Change from base Build 25:	-0.9%
Covered Lines:	38
Relevant Lines:	66

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 28

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• 4 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.9%) to 57.576%

---

Files with Coverage Reduction	New Missed Lines	%
zmq.hpp	4	65.33%

Totals
Change from base Build 25:	-0.9%
Covered Lines:	38
Relevant Lines:	66

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 29

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• 4 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-2.2%) to 56.25%

---

Files with Coverage Reduction	New Missed Lines	%
zmq.hpp	4	64.38%

Totals
Change from base Build 25:	-2.2%
Covered Lines:	36
Relevant Lines:	64

---

💛 - Coveralls