resize x86 rootfs to 36 MB and kernel to 16 MB

This will allow x86 devices with 256 MB disk to upgrade.
3 jobs for v2018.2.3-ffs0.1 in 2 minutes and 18 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
failed #982
build

00:02:18

 
  Test
skipped #984
allowed to fail
code_quality
skipped #983
test
 
Name Stage Failure
failed
build Build
Step 4/11 : ENV USER=herokuishuser
---> Running in f6b855d4f250
Removing intermediate container f6b855d4f250
---> 342d9452ee4d
Step 5/11 : RUN /bin/herokuish buildpack build
---> Running in 90340150778b
-----> Unable to select a buildpack
The command '/bin/sh -c /bin/herokuish buildpack build' returned a non-zero code: 1
ERROR: Job failed: exit code 1