Add back --insecure option to CURL debug

This was added in review: https://review.openstack.org/#/c/53500 but
lost in the conversion to using session. Add it back again.

Change-Id: Ia063eb018d3a7da706a02d60df63bfa1be21d147
Related-Bug: #1249891
Fix debug curl commands for included data

Include the submitted data in the curl debug statement.
Initially fixed in: https://review.openstack.org/#/c/53501

Change-Id: I4e3e9e4799a508666fb37fafe864eea25b676836
Closes-Bug: #1249891
Sync openstack/common/memorycache.py with Oslo

This fixes an issue in Client.get(), where a dictionary was modified as we
iterated on its keys, which does not work in Python 3.

Change-Id: I37583504dcc672060a3d780dce46418baa32dd53
Python: Pass bytes to derive_keys()

This call was missed in d71b5b3.

Change-Id: I0705dbefa5893e0ff5b786202f58fb254939ae76
Merge "Sync openstack/common/memorycache.py with Oslo"
Merge "Python: Pass bytes to derive_keys()"
Merge "Add back --insecure option to CURL debug"
Merge "Fix debug curl commands for included data"