TS-2415: use standard continuations to release UrlRewrite objects

UrlRewrite uses a custom continuation to release the old object
after it is no longer needed. We can use library code for this
instead. Use new_Deleter to free the old UrlRewrite object.
TS-1815: Add thread number and port to accept thread name
TS-1815: Add the file descriptor number to ET_AIO thread names
Add CHANGES for TS-2347
TS-2335: getting ts_lua to compile without warnings
TS-1815: Change ET_AIO thread name layout for consistency
TS-2416: configurable TLS session timeout threshold

Default is 300 seconds. It's good to be configurable so that
application can specify the threshold for the expiration of internal
session and session ticket.
TS-2351 Make the Range calculations more resilient
TS-2372: update default SSL context options
TS-2372: enable ECDHE forward security
Add missing colon
Clarify anonymize_other_header_list
Add in examples
TS-2372 Fix typo in npnEndpoint
TS-2335: some more fixes for compile warning for ts_lua plugin
TS-2372: include openssl/ec.h
TS-2372: improved OpenSSL EC key support detection
TS-2372 Make ecdh CTX prototype follow SNI, and fix unused ctx on some platforms
TS-2384: Regression in key-lookup code between 4.0.x and 4.1.x

Revert "TS-302: Fix HTTPCacheAlt to use INK_MD5 directly instead of arrays of uin32_t. Simplify methods because of this."

This reverts commit c40c601c9167c4937f972daf7825821e527a5f67.

This breaks cache keys on certain builds. It's not clear why, but we
should remove this from 4.1.x so that we can have a stable release.
TS-2420: Remove STAT_SYNC, CONF_SYNC, and REM_SYNC threads and schedule
those continuations in ET_TASK