documentation

[ZBXNEXT-276] LDAP/SAML user provisioning (API).

Merge in WEB/documentation from feature/ZBXNEXT-276-6.4-D-API to release/6.4

* commit '4d2c397d1dd0143be307617d67e3d9b20fb007ab':
  [ZBXNEXT-276] Reverted update in "user.provision"
  [ZBXNEXT-276] Fixed 3 links; minor formatting updates
  [ZBXNEXT-276] Updated multiple API pages
  [ZBXNEXT-276] Updated table formatting on User directory API page
  [ZBXNEXT-276] Updated multiple API pages
  [ZBXNEXT-276] Formatting updates
  [ZBXNEXT-276] Updates to user.create/.update
  [ZBXNEXT-276] Updated "Appendix", reordered props, reformatted tables
  [ZBXNEXT-276] Updated User directory API
  [ZBXNEXT-276] Updated User group API, Authentication API
  [ZBXNEXT-276] Updated User API
  [ZBXNEXT-276] Updated User directory API
  [ZBXNEXT-276] Updated links in User API
  [ZBXNEXT-276] Updated User group API
  [ZBXNEXT-276] Updated User API
  [ZBXNEXT-276] Updated formatting
  [ZBXNEXT-276] Updated Authentication API, User directory API
  [ZBXNEXT-276] Updated User directory API
  [ZBXNEXT-276] Updated User API