Decouple COIN scripts from project scripts

We are thinking of using COIN in a several different projects (not related to Qt),
but see a few potential issues regarding the scripts located in the /coin folder.

Here would be a few of them:

1. How to easily include /coin into new projects?

On Windows, the copy-paste solution for the scripts, needs additional git tweaking for
the Linux executable flags. Also probably a central place ("authority") for these files
would be needed, and maybe some versioning.

2. How to update scripts in existing projects and branches?

The COIN infrastructure can change for various reasons, and then an update in all projects
might be needed. Although the projects themselves don't need any update.
In some cases, this might not be even possible, for example the locked release branches.

3. How to share the scripts between different multiple projects?

There are already some very nice shared scripts, but how to add new ones and how to
distribute them to all other projects. What about versioning of these scripts?

Maybe there are some more potential issues, but for now this is probably enough to illustrate the problem.

Proposal

A suggestion for a possible solution could be the separation of scripts that are needed
for COIN, and those that are needed for projects. A project could only have the scripts
which are only related to that particulate project, and nothing else.

During provisioning and pri-provisioning , COIN could pull the scripts, and script library
from some other locations/repositories.