rebase to alpine 3.8 and use buildstage type build

list

@@ -1,6 +0,0 @@
-COPY --from=buildstage /tmp/comskip-build/usr/ /usr/
-COPY --from=buildstage /tmp/argtable-build/usr/ /usr/
-COPY --from=buildstage /tmp/tvheadend-build/usr/ /usr/
-COPY --from=buildstage /tmp/xmltv-build/usr/ /usr/
-COPY --from=buildstage /usr/local/share/man/ /usr/local/share/man/
-COPY --from=buildstage /usr/local/share/perl5/ /usr/local/share/perl5/