Prior to this patch, you removed header metadata (such as
x-account-meta-name or x-container-meta-name) by sending the header
with no value. However, many tools such as curl will not send headers
with empty values.
This patch adds an alternate method for header metadata removal: Send
an x-remove-account-meta-name (x-remove-container-meta-name) header
with any value and the proxy will translate it to the original header
name with no value, indicating removal.
For safety, if you specify both x-remove-account-meta-name and
x-account-meta-name headers in the same request, the -remove header
will be ignored.
Change-Id: Ic220bec05a0e266db85fc8fa50011146ee886d9c
abc6313e35