Fix dockerfile w/ GoogleContainerTools/kaniko#742

Dockerfile

@@ -5,11 +5,7 @@ MAINTAINER bluespacecanary
 
 # create a new empty shell project
 RUN USER=root cargo new --bin rustbucket
-WORKDIR /home/rust/src/rustbucket
-
-# copy over your manifests
-COPY ./Cargo.lock ./Cargo.lock
-COPY ./Cargo.toml ./Cargo.toml
+ADD --chown=rust:rust ./ .
 
 # this build step will cache your dependencies
 # Optimization to make it less annoying to tinker with cargo build
@@ -18,7 +14,7 @@ RUN cargo build --release
 RUN rm src/*.rs
 
 # copy your source tree
-COPY ./src ./src
+COPY ./src ./src/
 
 # build for release
 RUN cargo build --release