Clang-format sees the text behind `#pragma region` as code and formats it. Instead of stating the copyright and date there, it's now in the comment block right below it. The text "Copyright" is left in the `#pragma region` line, as clang-format sees it as a single identifier.
I took the opportunity to normalize the dates, and add the copyright notice to the source files where it was missing them (except for third-party and the generated resources.h file).
Predefined title sequence filenames are now treated as "reserved".
Custom title sequences cannot use reserved names and an error will
appear if the user tries.
Duplicating predefined title sequence now uses default text of
predefined sequence's proper name instead of filename.
Renamed `WIDX_TITLE_EDITOR_RENAME_SAVE_BUTTON` to
`WIDX_TITLE_EDITOR_RENAME_BUTTON` to follow formatting of other preset
button ids.
Added string id 6154, `STR_ERROR_RESERVED_NAME`, "Name is reserved".
