moblab-ui:  Stop ngix restarting constantly.

Incorrect permissions / missing directories in
/var/cache/nginx fixed.
Opened up the /var/run dir for write so pid file can be written.

Cleaned up the nginx.conf to remove warning messages should
make it easier to see real issues in the logs.

BUG=
TEST=local build and test.

Change-Id: I0e1a50bdbfd8413385ca833e0ae3c67f3ef80998
2 files changed