Rename .log to .log.txt in run-tox
Rename .log to .log.txt in run-tox

Apache knows .txt files are text/plain by default, but doesn't know
what to make of .log files. Rather than hack encoding overrides into
our logserver vhost, just rename the log files by tox only
in run-tox.sh before uploading so that they can be served properly.

Change-Id: I03cba279037259fcaa5073d67caf23662b3a59d2

noorul/os-project-config,Tesora/tesora-project-config,dongwenjuan/project-config,openstack-infra/project-config,openstack-infra/project-config,dongwenjuan/project-config,noorul/os-project-config,Tesora/tesora-project-config