Use `${MIRROR}` in update
Merge pull request #2 from jbergstroem/update_mirror

Use `${MIRROR}` in update
Strip entr before installing
Merge pull request #4 from jbergstroem/entr_strip

Strip entr before installing
Bumped DATE to 20141106.
Update oracle jre/jdk download urls to 7u71.
Set default locale/timezone. #3
Create root home dir.
Add BOB_* variables as ENVs to build container. Enables passing of vars from build.sh to build-root.sh in bob.
Set php timezone.
Increase innodb_buffer_pool_size and innodb_data_file_path max size.
Purge /usr/share/i18n and /usr/lib64/gconv. #3
Add dev-libs/gmp, required for ruby21.
Remove unnecessary -r option from rm statements. #10
Move entr binary from busybox to s6 image, closes #9.
Updated docs.
Redirect eselect warnings.
Backup headers and static libs before they are purged, add HEADERS_FROM and STATIC_LIBS_FROM to enable import by other images. #6
Bump DATE to 20141113. Set BOB_TIMEZONE default to UTC.
Only update DATE if a newer stage3 release is found.