Merge pull request #9757 from s0undt3ch/develop

Don't fail badly on setting VT screen size. Refs #9742.
Merge pull request #9759 from s0undt3ch/develop

Some more VT fixes
Add trace log to time master function calls
Change yum module to not nuke the package cache every state run

This change mirrors the behavior in the apt module. Previous behavior of
nuking the package cache would cause yum to download ~30 MB of data for
each and every highstate run.
Merge pull request #9764 from whiteinge/yum-refresh-db-fix

Change yum module to not nuke the package cache every state run
fileserver/roots.py: rm unused import of `time` module

************* Module salt.fileserver.roots
salt/fileserver/roots.py:11: [W0611(unused-import), ] Unused import time
Merge pull request #9769 from cvrebert/patch-1

fileserver/roots.py: rm unused import of `time` module
`child_fd` is not a file handle!