docker: update hub dockerfile (#9173)

* update Dockerfile for hub

update to Ubuntu Xenial 16.04
fix cmake version

* docker: fix tab indentation in hub dockerfile

Author: andresilva

docker/hub/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:14.04
+FROM ubuntu:xenial
 MAINTAINER Parity Technologies <devops@parity.io>
 WORKDIR /build
 #ENV for build TAG
@@ -40,7 +40,6 @@ cd /build&&git clone https://github.com/paritytech/parity && \
 	git pull&& \
 	git checkout $BUILD_TAG && \
         cargo build --verbose --release --features final && \
-        #ls /build/parity/target/release/parity && \
         strip /build/parity/target/release/parity && \
  file /build/parity/target/release/parity&&mkdir -p /parity&& cp /build/parity/target/release/parity /parity&&\
 #cleanup Docker image
@@ -51,6 +50,7 @@ cd /build&&git clone https://github.com/paritytech/parity && \
         # add-apt-repository
         software-properties-common \
         make \
+        cmake \
         curl \
         wget \
         git \