[SUSTAIN-663] Update Content-Length in header only if the response is not 1xx or 204.
[SUSTAIN-663] Update Content-Length in header only if the response is not 1xx or 204.

Signed-off-by: Prajakta Purohit <e0b6074fb36005ab38b637036277c00627bb386c@opscode.com>

chef/webmachine,chef/webmachine