fix qmake command and add ccache to i686 image

docker/manylinux2014/Dockerfile_i686

@@ -49,6 +49,13 @@ RUN cd ~/ffmpeg_sources && \
     ldconfig && \
     rm -rf ~/ffmpeg_sources
 
+RUN curl -O -L https://github.com/ccache/ccache/releases/download/v3.7.9/ccache-3.7.9.tar.gz && \
+    tar -xf ccache-3.7.9.tar.gz && \
+    cd ccache-3.7.9 && \
+    linux32 ./configure && \
+    make -j$(getconf _NPROCESSORS_ONLN) && \
+    make install
+
 ENV PKG_CONFIG_PATH /usr/local/lib/pkgconfig:/root/ffmpeg_build/lib/pkgconfig
 ENV LDFLAGS -L/root/ffmpeg_build/lib
 ENV PATH "$HOME/bin:$PATH"

travis_config.sh

@@ -104,6 +104,8 @@ function pre_build {
         export PATH="/usr/local/opt/qt/bin:$PATH"
     fi
 
+    qmake -query
+
     echo 'Installing FFmpeg'
 
     if [ -n "$CACHE_STAGE" ]; then
@@ -123,8 +125,8 @@ function pre_build {
 
   else
     echo "Running for linux"
+      qmake-qt5 -query
   fi
-  qmake -query
 }
 
 function run_tests {