Update Makefile use repository field intead of homepage field

[szabgab]

No description provided.

[jerome-jutteau]

Thanks for the PR, regeneration test seems to fail again. We will have a look a this. ping @outscale-mgo

[outscale-mgo]

Hello, I think, this PR should be merged with, #36.
Otherwise, the makefile will generate Cargo.toml, but compare it to the old one, with homepage, and so fail.
Also, in the other PR, you add a \n at the end of Cargo.toml, my guess, is that it should be remove, or the regenerate will fail again.

[outscale-mgo]

see #38