##### 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)]
```

roles_left.append(dep_role)
                                else:
                                    display.warning('- dependency %s (%s) from role %s differs from already installed version (%s), skipping' %
                                                    (to_text(dep_role), dep_role.version, role.name, dep_role.install_info['version']))
                            else:
                                if force_deps:
                                    roles_left.append(dep_role)
                                else:
                                    display.display('- dependency %s is already installed, skipping.' % dep_role.name)
            if not installed:
                display.warning("- %s was NOT installed successfully." % role.name)
                self.exit_without_ignore()
        return 0
    def execute_remove(self):
        """
        removes the list of roles passed as arguments from the local system.
        """
        if not context.CLIARGS['args']:
            raise AnsibleOptionsError('- you must specify at least one role to remove.')
        for role_name in context.CLIARGS['args']:
            role = GalaxyRole(self.galaxy, self.api, role_name)
            try:
                if role.remove():
                    display.display('- successfully removed %s' % role_name)
                else:
                    display.display('- %s is not installed, skipping.' % role_name)
            except Exception as e:
                raise AnsibleError("Failed to remove role %s: %s" % (role_name, to_native(e)))
        return 0
    def execute_list(self):