Wrong usage of "an" in the messages:
"the optional os_options paramater includes an non-empty"
"We are allowing to have an tenant_name argument"
Should be:
"the optional os_options paramater includes a non-empty"
"We are allowing to have a tenant_name argument"
Totally 2 occurrences in python-swiftclient base code.
Change-Id: I2f2f7e07432fedfee5ccb418d9505250b3fed597