##### SUMMARY
`ansible-galaxy collection install` currently requires the user to specify an install path using the `-p` option. Galaxy currently generates and displays the CLI command for installing a collection. There is no way for Galaxy to determine a value for `-p`, and hard coding a default value into Galaxy makes no sense.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
`ansible-galaxy`

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```
ansible 2.10.0.dev0
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/Users/chouseknecht/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /Users/chouseknecht/projects/ansible/lib/ansible
  executable location = /Users/chouseknecht/.pyenv/versions/venv27/bin/ansible
  python version = 2.7.14 (default, Nov 14 2017, 23:24:24) [GCC 4.2.1 Compatible Apple LLVM 9.0.0 (clang-900.0.38)]
```

list_parser = parser.add_parser('list', parents=parents,
                                        help='Show the name and version of each role installed in the roles_path.')
        list_parser.set_defaults(func=self.execute_list)
        list_parser.add_argument('role', help='Role', nargs='?', metavar='role')
    def add_search_options(self, parser, parents=None):
        search_parser = parser.add_parser('search', parents=parents,
                                          help='Search the Galaxy database by tags, platforms, author and multiple '
                                               'keywords.')
        search_parser.set_defaults(func=self.execute_search)
        search_parser.add_argument('--platforms', dest='platforms', help='list of OS platforms to filter by')
        search_parser.add_argument('--galaxy-tags', dest='galaxy_tags', help='list of galaxy tags to filter by')
        search_parser.add_argument('--author', dest='author', help='GitHub username')
        search_parser.add_argument('args', help='Search terms', metavar='searchterm', nargs='*')
    def add_import_options(self, parser, parents=None):
        import_parser = parser.add_parser('import', parents=parents, help='Import a role')
        import_parser.set_defaults(func=self.execute_import)
        import_parser.add_argument('--no-wait', dest='wait', action='store_false', default=True,
                                   help="Don't wait for import results.")
        import_parser.add_argument('--branch', dest='reference',
                                   help='The name of a branch to import. Defaults to the repository\'s default branch '
                                        '(usually master)')
        import_parser.add_argument('--role-name', dest='role_name',
                                   help='The name the role should have, if different than the repo name')
        import_parser.add_argument('--status', dest='check_status', action='store_true', default=False,
                                   help='Check the status of the most recent import request for given github_'
                                        'user/github_repo.')
    def add_setup_options(self, parser, parents=None):