Fix screwed up progress bars in Travis output
Created by: ollieparanoid
Changes
Disabling the progress bars in abuild works just like Alpine does it in
their Travis CI script: Exporting SUDO_APK
as
"abuild-apk --no-progress" instead of "abuild-apk".
test_check_checksums.py: Run "pmbootstrap build_init" before building any packages, so it is a bit less verbose (downloading the APKINDEX files etc.). Later we run the build init code again (because we use --strict while building the packages), but then the APKINDEX files are already present. So overall the log is a bit shorter before the building starts. (It is still logged to the logfile, which gets printed on error anyway.)