How to install GitZilla with GitLab and Bugzilla

Question

I have a setup with GitLab (the latest version) and Bugzilla 4.4.1 installed on a CentOS machine. Users create local repositories on their systems and push to a central repository, i.e., on GitLab. I need to setup bug tracking with Gitab, so that each push updates Bugzilla with all the commits to the project.

I found that Gitzilla is used for such a thing, but after going through its installation instructions, I failed to understand one of the points.

Switch to the hooks directory (/path/to/repository/.git/hooks) and delete the post-receive and update hooks.

Link (or copy) the gitzilla provided hooks:
ln -s $(which gitzilla-post-receive) post-receive
ln -s $(which gitzilla-update) update

For example, if a user logs into GitLab and creates a new project named samplerepo, then on my git account on CentOS under repositores I get the following two entries:

/home/git/repositories/user/samplerepo.git
/home/git/repositories/user/samplerepo.wiki.git

where, user = the user who created the project.

So the problems faced are:

1. Where are the post_recieve and updates hooks as mentioned in the installation steps? I navigated to the hooks directory inside the samplerepo.git folder and found no such file, only a bunch of .sample files.
2. If suppose a 100 users create several projects, each of them will have the *.git and *.wiki.git folders under their usernames in repositories, will I need to setup hooks in every project's *.git folder? Isn't there any central location where I can add those hooks?

Any help is much appreciated.