Generate manpage in build

[ansasaki]

This adds the manpage generation to Makefile and to tox.ini.

[codecov-io]

Codecov Report

Merging #78 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #78   +/-   ##
=======================================
  Coverage   97.56%   97.56%           
=======================================
  Files           4        4           
  Lines         740      740           
  Branches      190      190           
=======================================
  Hits          722      722           
  Partials       18       18

---

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[coveralls]

Pull Request Test Coverage Report for Build 167

• 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 98.489%

---

Totals
Change from base Build 165:	0.0%
Covered Lines:	740
Relevant Lines:	740

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 167

• 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 98.489%

---

Totals
Change from base Build 165:	0.0%
Covered Lines:	740
Relevant Lines:	740

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 167

• 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 98.489%

---

Totals
Change from base Build 165:	0.0%
Covered Lines:	740
Relevant Lines:	740

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 167

• 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 98.489%

---

Totals
Change from base Build 165:	0.0%
Covered Lines:	740
Relevant Lines:	740

---

💛 - Coveralls