openssl_encrypt with no 5th argument is failing

[moufmouf]

See #76.

PR starts with a failing test.

[coveralls]

Pull Request Test Coverage Report for Build 163

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 35.436%

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Totals
Change from base Build 160:	0.0%
Covered Lines:	191
Relevant Lines:	539

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 163

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 35.436%

---

Totals
Change from base Build 160:	0.0%
Covered Lines:	191
Relevant Lines:	539

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 177

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 19 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.2%) to 35.78%

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Files with Coverage Reduction	New Missed Lines	%
src/Method.php	19	46.24%

Totals
Change from base Build 176:	0.2%
Covered Lines:	195
Relevant Lines:	545

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💛 - Coveralls