functional,tests: git mv functional tests/

Modularization: Mechanical move of "functional" directory into tests module using:

% git mv functional tests/

tests/functional/Dockerfile

@@ -0,0 +1,42 @@
+FROM fedora:28
+
+RUN dnf check-update || true \
+  && dnf install --assumeyes \
+  git curl wget mercurial meld gcc gcc-c++ which \
+  gcc automake autoconf dh-autoreconf libtool libtool-ltdl \
+  tar unzip gzip \
+  && dnf check-update || true \
+  && dnf upgrade --assumeyes || true \
+  && dnf autoremove --assumeyes || true \
+  && dnf clean all || true
+
+ENV GOROOT /usr/local/go
+ENV GOPATH /go
+ENV PATH ${GOPATH}/bin:${GOROOT}/bin:${PATH}
+ENV GO_VERSION REPLACE_ME_GO_VERSION
+ENV GO_DOWNLOAD_URL https://storage.googleapis.com/golang
+RUN rm -rf ${GOROOT} \
+  && curl -s ${GO_DOWNLOAD_URL}/go${GO_VERSION}.linux-amd64.tar.gz | tar -v -C /usr/local/ -xz \
+  && mkdir -p ${GOPATH}/src ${GOPATH}/bin \
+  && go version
+
+RUN mkdir -p ${GOPATH}/src/go.etcd.io/etcd
+ADD . ${GOPATH}/src/go.etcd.io/etcd
+ADD ./functional.yaml /functional.yaml
+
+RUN go get -v go.etcd.io/gofail \
+  && pushd ${GOPATH}/src/go.etcd.io/etcd \
+  && GO_BUILD_FLAGS="-v" ./build \
+  && mkdir -p /bin \
+  && cp ./bin/etcd /bin/etcd \
+  && cp ./bin/etcdctl /bin/etcdctl \
+  && GO_BUILD_FLAGS="-v" FAILPOINTS=1 ./build \
+  && cp ./bin/etcd /bin/etcd-failpoints \
+  && ./functional/build \
+  && cp ./bin/etcd-agent /bin/etcd-agent \
+  && cp ./bin/etcd-proxy /bin/etcd-proxy \
+  && cp ./bin/etcd-runner /bin/etcd-runner \
+  && cp ./bin/etcd-tester /bin/etcd-tester \
+  && go build -v -o /bin/benchmark ./tools/benchmark \
+  && popd \
+  && rm -rf ${GOPATH}/src/go.etcd.io/etcd