Fix backend specific implementations

* After the rebase the import syntax needed to be changed to rust2018

Author: weiznich

diesel/src/mysql/query_builder/limit_offset.rs

@@ -1,9 +1,9 @@
-use mysql::Mysql;
-use query_builder::limit_clause::{LimitClause, NoLimitClause};
-use query_builder::limit_offset_clause::{BoxedLimitOffsetClause, LimitOffsetClause};
-use query_builder::offset_clause::{NoOffsetClause, OffsetClause};
-use query_builder::{AstPass, IntoBoxedClause, QueryFragment};
-use result::QueryResult;
+use crate::mysql::Mysql;
+use crate::query_builder::limit_clause::{LimitClause, NoLimitClause};
+use crate::query_builder::limit_offset_clause::{BoxedLimitOffsetClause, LimitOffsetClause};
+use crate::query_builder::offset_clause::{NoOffsetClause, OffsetClause};
+use crate::query_builder::{AstPass, IntoBoxedClause, QueryFragment};
+use crate::result::QueryResult;
 
 impl QueryFragment<Mysql> for LimitOffsetClause<NoLimitClause, NoOffsetClause> {
     fn walk_ast(&self, _out: AstPass<Mysql>) -> QueryResult<()> {

diesel/src/pg/query_builder/limit_offset.rs

@@ -1,7 +1,7 @@
-use pg::Pg;
-use query_builder::limit_offset_clause::{BoxedLimitOffsetClause, LimitOffsetClause};
-use query_builder::{AstPass, IntoBoxedClause, QueryFragment};
-use result::QueryResult;
+use crate::pg::Pg;
+use crate::query_builder::limit_offset_clause::{BoxedLimitOffsetClause, LimitOffsetClause};
+use crate::query_builder::{AstPass, IntoBoxedClause, QueryFragment};
+use crate::result::QueryResult;
 
 impl<'a, L, O> IntoBoxedClause<'a, Pg> for LimitOffsetClause<L, O>
 where

diesel/src/sqlite/query_builder/limit_offset.rs

@@ -1,9 +1,9 @@
-use query_builder::limit_clause::{LimitClause, NoLimitClause};
-use query_builder::limit_offset_clause::{BoxedLimitOffsetClause, LimitOffsetClause};
-use query_builder::offset_clause::{NoOffsetClause, OffsetClause};
-use query_builder::{AstPass, IntoBoxedClause, QueryFragment};
-use result::QueryResult;
-use sqlite::Sqlite;
+use crate::query_builder::limit_clause::{LimitClause, NoLimitClause};
+use crate::query_builder::limit_offset_clause::{BoxedLimitOffsetClause, LimitOffsetClause};
+use crate::query_builder::offset_clause::{NoOffsetClause, OffsetClause};
+use crate::query_builder::{AstPass, IntoBoxedClause, QueryFragment};
+use crate::result::QueryResult;
+use crate::sqlite::Sqlite;
 
 impl QueryFragment<Sqlite> for LimitOffsetClause<NoLimitClause, NoOffsetClause> {
     fn walk_ast(&self, _out: AstPass<Sqlite>) -> QueryResult<()> {