docs: add CURLOPT type change history, drop casts where present

[vszakats]

Some CURLOPT constants defined in the curl public headers were initially
enums (= ints), or macros with bare numeric values. Recent curl releases
upgraded them to long constants, to make them pass correctly to
curl_easy_setop() by default, i.e. without requiring a (long) cast.

This patch drops such casts from the examples embedded in the docs. At
the same time it documents which curl release made them long types,
to keep them useful when working with previous libcurl versions.

Also:

• drop a (long) cast that was never necessary.
• CURLOPT_ALTSVC_CTRL.md: bump local copy of macros to long.
• test1119: make it ignore symbols ending with an underscore, to skip
  wildcard, e.g. **CURLAUTH_***.

---

• replace (long) cast with L suffix for CURLHSTS_* macros. → moved to separate commit d1da954
• merge a couple of remaining macro updates and update this PR with them.
  → CURLOPT: bump remaining macros to long #18134
  → CURLOPT: bump CURL_SSLVERSION_* macros to long #18135
  → CURLOPT: bump CURLPROTO_* macros to long #18136
  → CURLOPT: bump CURLWS_NOAUTOPONG, CURLWS_RAW_MODE macros to long #18137