remove DbConn from PlumeRocket

this means compilation fails, and for the next while, we'll try to make
it compile again ;)

plume-models/src/plume_rocket.rs

@@ -2,7 +2,7 @@ pub use self::module::PlumeRocket;
 
 #[cfg(not(test))]
 mod module {
-    use crate::{db_conn::DbConn, search, users};
+    use crate::{search, users};
     use rocket::{
         request::{self, FlashMessage, FromRequest, Request},
         Outcome, State,
@@ -12,7 +12,6 @@ mod module {
 
     /// Common context needed by most routes and operations on models
     pub struct PlumeRocket {
-        pub conn: DbConn,
         pub intl: rocket_i18n::I18n,
         pub user: Option<users::User>,
         pub searcher: Arc<search::Searcher>,
@@ -24,14 +23,12 @@ mod module {
         type Error = ();
 
         fn from_request(request: &'a Request<'r>) -> request::Outcome<PlumeRocket, ()> {
-            let conn = request.guard::<DbConn>()?;
             let intl = request.guard::<rocket_i18n::I18n>()?;
             let user = request.guard::<users::User>().succeeded();
             let worker = request.guard::<'_, State<'_, Arc<ScheduledThreadPool>>>()?;
             let searcher = request.guard::<'_, State<'_, Arc<search::Searcher>>>()?;
             let flash_msg = request.guard::<FlashMessage<'_, '_>>().succeeded();
             Outcome::Success(PlumeRocket {
-                conn,
                 intl,
                 user,
                 flash_msg: flash_msg.map(|f| (f.name().into(), f.msg().into())),
@@ -54,7 +51,6 @@ mod module {
 
     /// Common context needed by most routes and operations on models
     pub struct PlumeRocket {
-        pub conn: DbConn,
         pub user: Option<users::User>,
         pub searcher: Arc<search::Searcher>,
         pub worker: Arc<ScheduledThreadPool>,
@@ -64,12 +60,10 @@ mod module {
         type Error = ();
 
         fn from_request(request: &'a Request<'r>) -> request::Outcome<PlumeRocket, ()> {
-            let conn = request.guard::<DbConn>()?;
             let user = request.guard::<users::User>().succeeded();
             let worker = request.guard::<'_, State<'_, Arc<ScheduledThreadPool>>>()?;
             let searcher = request.guard::<'_, State<'_, Arc<search::Searcher>>>()?;
             Outcome::Success(PlumeRocket {
-                conn,
                 user,
                 worker: worker.clone(),
                 searcher: searcher.clone(),