Pyfortimanager

Bug Fixes
- **FortiGates:** Fixed `adom` variable not being used when using the `upgrade` function.

Breaking Changes
- **FortiAPs:** The `add` function has been replaced by `add_to_fortigate` and `add_to_adom`, along with its subsequent update and delete functions.
This also matches the same behaviour as for FortiSwitches.

New Features
- Added `adom` argument for the `upgrade` method under **FortiGates**.

Bug Fixes
- `adom` argument was not sent in the request for the `execute` method under **Scripts**.

Breaking Changes
`pyfortimanager` no longer supports the legacy session based login method.
The new login method is token based as of FortiManager v7.2.2. [Documentation](https://docs.fortinet.com/document/fortimanager/7.2.0/new-features/47777/fortimanager-supports-authentication-token-for-api-administrators-7-2-2).

New Features
- **FortiSwitches (Proxy):** Added support for restarting a FortiSwitch.
- **Policy Packages:** Added support for adding/updating/moving/cloning/deleting a policy package.
- **Policy Packages:** Added support for adding/updating/deleting a folder.
- **System:** Added a function for calling a custom API endpoint, `FortiManager.system.custom_request()`.

Other Changes
- Updated `README.md` documentation.

Breaking Changes
`pyfortimanager` now no longer supports FortiManager v7.0.x.
The supported version is now FortiManager v7.2.x.

New Features
- **Metadata Variables:** Added support for metadata variables and dynamic mapping.

Other Changes
- **FortiAPs:** Added `is_model` to add method.
- **FortiSwitches:** Added `is_model` and `state` to add method.

New Features
- **FortiAPs (Proxy):** Added `restart` method.

Other Changes
- Formatted python files