Preserve the comments of the "cli.toml" on changes

[mamcx]

Description of Changes

We would like to preserve a user's manual edits, including comments, so now 'tolm_edit' is used for mutating the config file.

Closes #1798.

API and ABI breaking changes

Marked breaking because of the change of crate to parse and save. Is the low-level used by 'toml'.

Expected complexity level and risk

2:

Marked breaking because of the change of how to parse and save the file (that mutates instead of generating a fresh immutable view of the config) even if according to test there is none.

Testing

• Write unit testing that simulates different edits.
• Run 'standalone' and execute several 'cli' commands to see manually if the config was updated without issues.

[bfops]

nit: Should we have a ServerConfig::from_table? (or an impl From<&Table> for ServerConfig or something)

[bfops]

    pub fn from_table:(table: &Table) -> Self {
        let nickname = table.get("nickname").and_then(Item::as_str).map(String::from);
        let host = table.get("host").and_then(Item::as_str).map(String::from).unwrap();
        let protocol = table.get("protocol").and_then(Item::as_str).map(String::from).unwrap();
        let ecdsa_public_key = table.get("ecdsa_public_key").and_then(Item::as_str).map(String::from);
        ServerConfig {
            nickname,
            host,
            protocol,
            ecdsa_public_key,
        }
    }

[bfops]

nit: can we do something like let RawConfig { ... } = home so people don't forget to update this function if they add more fields?