sdo README-1.11 various issues

[SanjeevKGupta]

Refer this doc

https://github.com/open-horizon/SDO-support/blob/master/README-1.11.md

A. Missing step to set KEY_NAME ENV
In section Generate Owner Key Pairs, step 1 uses an ENV variable KEY_NAME but document prior to this step does not mention anywhere to create such ENV variable. Suggest documenting this step.

B. Missing sudo -E
In section, Boot the Device to Have it Configured, step 2 prepend sudo -E as access to /var/log/syslog is permission denied

sanjeev@ieam-edge-sdo:~/sdo$ hzn service log -f ibm.helloworld
Found service ibm.helloworld with service id 910ef075bce51ff6174e373e3ebaf5526751dac8bb8770c881b323dfdad8cdf7.
Displaying log messages of container ibm.helloworld for service ibm.helloworld with service id 910ef075bce51ff6174e373e3ebaf5526751dac8bb8770c881b323dfdad8cdf7.
Use ctrl-C to terminate this command.
Error: /var/log/syslog could not be opened or does not exist: open /var/log/syslog: permission denied