Add function management

[rdunklau]

Closes #30

I add to tweak the way object names are represented along the way.
Also, I noticed that the tests were failing on PG > 10, so I fixed that too.

I added minimal test coverage to the existing suite, I hope it's sufficient.

[coveralls]

Pull Request Test Coverage Report for Build 225

• 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 96.629%

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Totals
Change from base Build 224:	0%
Covered Lines:	1290
Relevant Lines:	1335

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💛 - Coveralls

[rdunklau]

Any news on this PR ?

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