Package compilation fails at lazpackagerbase.pas(289,13) Error: Identifier not found "CreateRelativePath"

[Cigydd]

If I try to compile the package, I get the following error:
lazpackagerbase.pas(289,13) Error: Identifier not found "CreateRelativePath"

Apparently, the FileUtil unit isn’t included in the uses clause.

Commit "gitignore .project" (commited at 2016-09-30)

Edit: No no, the unit is used. Why am I getting this error?
Edit2: On Lazarus 1.8.4, Linux Mint 19 Tara x86_64

[tandriamirado]

Solved.. @prof7bit has to accept the pull request.
In the meantime: https://github.com/tandriamirado/LazPackager
Some functions had been moved, so 2 units were included in the uses clause. Enjoy ;)