add fedora docker image to travis compilation (#3447)

* add fedora docker image to travis compilation

fixes #1746

* add dockerfile

* would you like to please install for me? [y/n]

* remove bc dependency

* save cache separately for different docker builds

* add development packages to fedora dockerfile

* add package names

* use env values to make these all look the same

* set docker image name correctly

* add missing dependency

* minor oversight, add %% to remove all braces in check schema

.ci/Fedora29/Dockerfile

@@ -0,0 +1,17 @@
+FROM fedora:29
+
+RUN dnf install -y \
+        @development-tools \
+        ccache \
+        cmake \
+        desktop-file-utils \
+        file \
+        gcc-c++ \
+        hicolor-icon-theme \
+        libappstream-glib \
+        protobuf-devel \
+        qt5-{qttools,qtsvg,qtmultimedia,qtwebsockets}-devel \
+        sqlite-devel \
+        wget \
+        zlib-devel \
+    && dnf clean all

.ci/UbuntuBionic/Dockerfile

@@ -1,7 +1,6 @@
 FROM ubuntu:bionic
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
-        bc \
         build-essential \
         clang-format \
         file \