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##### SUMMARY
The "source" folder of my collection contains several files that are not directly related to the collection itself. E.g. a `.gitignore`, a `.github` folder, a `Makefile` etc.
When using `ansible-galaxy collection build <folder>`, these files are included in the generated tarball. This is especially hurtful when the source folder also contains a Python venv that I use for developing.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
ansible-galaxy

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.9.0.dev0
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/home/egolov/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /home/egolov/Devel/ansible/ansible/lib/ansible
  executable location = /home/egolov/Devel/ansible/ansible/bin/ansible
  python version = 2.7.15 (default, Oct 15 2018, 15:26:09) [GCC 8.2.1 20180801 (Red Hat 8.2.1-2)]

```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
empty
```

##### OS / ENVIRONMENT
Fedora


##### STEPS TO REPRODUCE
Build a collection :)

##### EXPECTED RESULTS
I'd expect only collection-relevant files/folders (those that are listed in the spec/docs) to be included.


##### ADDITIONAL INFORMATION
Alternatively, a ignore file as suggested by @bcoca  in https://github.com/ansible/ansible/pull/59121/files#r304554334 could be a fix for this.

"""
        Supports version identifiers can be '==', '!=', '>', '>=', '<', '<=', '*'. Each requirement is delimited by ','
        """
        op_map = {
            '!=': operator.ne,
            '==': operator.eq,
            '=': operator.eq,
            '>=': operator.ge,
            '>': operator.gt,
            '<=': operator.le,
            '<': operator.lt,
        }
        for req in list(requirements.split(',')):
            op_pos = 2 if len(req) > 1 and req[1] == '=' else 1
            op = op_map.get(req[:op_pos])
            requirement = req[op_pos:]
            if not op:
                requirement = req
                op = operator.eq
                
                
                if parent and version == '*' and requirement != '*':
                    break
                elif requirement == '*' or version == '*':
                    continue
            if not op(LooseVersion(version), LooseVersion(requirement)):
                break
        else:
            return True