Milestone 5: deliver embedded RDP sessions and lifecycle hardening

third_party/FreeRDP/docs/README.timezones

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+## Timezone related options
+
+* WITH_TIMEZONE_COMPILED   Use compiled in mapping extracted with tzextract (default ON)
+* WITH_TIMEZONE_FROM_FILE  Use JSON file mapping generated with tzextract (default OFF)
+* WITH_TIMEZONE_ICU        Use ICU to map IANA to windows timezones (default OFF)
+* WITH_TIMEZONE_UPDATER    Build the tzextract utility (default OFF)
+
+### Suggested usage
+
+* WITH_TIMEZONE_COMPILED is suggested for single binary builds (aka fully static) binaries that
+  can not rely on external files to exist.
+* WITH_TIMEZONE_FROM_FILE is suggested for distribution packages as this allows updating timezone
+  mappings without a necessary recompile of the FreeRDP binaries. Set WITH_TIMEZONE_COMPILED=OFF
+  in such cases as both options can be used in combination. (entries from file taking preference
+  over compiled in versions)
+* WITH_TIMEZONE_ICU is suggested if the target is already linked against ICU. This eliminates a
+  required mapping table generated from WindowsZones.xml. This option is only a fallback if the
+  compiled in or loaded from file mappings do not match any.
+
+## Keeping timezone mappings up to date
+
+On an up to date windows machine run the following binary after a build with -DWITH_TIMEZONE_UPDATER=ON (from build directory):
+
+tzextract <path to source>\winpr\libwinpr\timezone
+
+After running the scripts check
+ * git clang-format -f to eliminate formatting changes
+ * winpr/libwinpr/timezone/WindowsZones.c
+for changes.
+
+on any machine run the following script from checkout root:
+
+./scripts/update-windows-zones.py
+
+After running the scripts check
+ * git clang-format -f to eliminate formatting changes
+ * winpr/libwinpr/timezone/WindowsZones.c
+for changes.
+
+Commit if the definitions changed:
+1. run `git clang-format -f` on these changed files
+2. commit these changes
+3. create a pull request at https://github.com/FreeRDP/FreeRDP