4609b861d1
Previously, 'If-Modified-Since' and 'If-Unmodified-Since' HTTP headers were incorrectly processed within from/to HTTP headers mapping, because Spring-Web `HttpHeaders` has a confusing method name, see: https://jira.springsource.org/browse/SPR-10600 * fix 'If-Modified-Since' and 'If-Unmodified-Since' processing independently from `HttpHeaders` * add fallback to formatted string for date ware HTTP headers * add Spring Integration HTTP proxy scenario test JIRA: https://jira.springsource.org/browse/INT-2995