Macro recursion decrease and other optimizations

- Decreased `recursion_limit` from 512 to 87
  Mainly done by optimizing the config macro's.
  This fixes an issue with the rust-analyzer which doesn't go beyond 128
- Removed Regex for masking sensitive values and replaced it with a map()
  This is much faster then using a Regex.
- Refactored the get_support_json macro's
- All items above also lowered the binary size and possibly compile-time
- Removed `_conn: DbConn` from several functions, these caused unnecessary database connections for functions who didn't used that at all
- Decreased json response for `/plans`
- Updated libraries and where needed some code changes
  This also fixes some rare issues with SMTP https://github.com/lettre/lettre/issues/678
- Using Rust 2021 instead of 2018
- Updated rust nightly

src/error.rs

@@ -73,7 +73,7 @@ make_error! {
     Serde(SerdeErr): _has_source, _api_error,
     JWt(JwtErr):     _has_source, _api_error,
     Handlebars(HbErr): _has_source, _api_error,
-    //WsError(ws::Error): _has_source, _api_error,
+
     Io(IoErr):       _has_source, _api_error,
     Time(TimeErr):   _has_source, _api_error,
     Req(ReqErr):     _has_source, _api_error,