Remove legacy linux docker

admin/linux/Dockerfile

@@ -1,22 +0,0 @@
-# This DockerFile is used to create the image used for Jenkins, the CI system (see Jenkinsfile)
-# It is not meant to be used to create the production packages.
-
-# Distro with Qt 5.6
-FROM ubuntu:yakkety
-
-RUN apt-get update -q && DEBIAN_FRONTEND=noninteractive apt-get install -q -y --no-install-recommends \
-        locales \
-        build-essential \
-        clang \
-        ninja-build \
-        cmake \
-        extra-cmake-modules \
-        libsqlite3-dev \
-        libssl-dev \
-        libcmocka-dev \
-        qt5-default \
-        qttools5-dev-tools \
-        libqt5webkit5-dev \
-        qt5keychain-dev \
-        kio-dev \
-    && apt-get clean

admin/linux/clean_tarball.sh

@@ -1,8 +0,0 @@
-#!/bin/sh
-
-rm -vrf admin/
-rm -vrf src/3rdparty/sqlite3   # FIXME: For CentOS6 we have to use our bundled sqlite
-rm -vrf binary/
-rm -vrf src/3rdparty/libcrashreporter-qt
-rm -vrf shell_integration/windows
-rm -vrf shell_integration/MacOSX