Documentation cleaning.
- Formatting and grammar edits on recently added docs.
- Added missing NPC header and script conf include from ea8ccfc.
- Moved ER model files to a separate folder ('doc/model/').

Fixed a typo in Wolfchev instance. (bugreport:9263)
http://rathena.org/board/tracker/issue-9263-wolfchevlaboratory-script-error/

Signed-off-by: Euphy <euphy.raliel@rathena.org>
Hunting Missions script update.
- Added check for deleted characters. (credits: @AnnieRuru)
- Modernized script syntax and improved readability.

Signed-off-by: Euphy <euphy.raliel@rathena.org>
TXT reference removal from emulator.
- Removed any remaining TXT and SQL references from files.
- The 'make sql' command is now replaced by 'make server'.
- Removed account.engine feature as it is no longer needed.
- Moved login and IP ban configs to inter_athena.conf.
- Cleaned up cmake files.
- Miscellaneous clean ups.
Follow up to 2d2991a. Fixed the set property function for login_codepage and login_case_sensitive configs.
Fix teleport typo cuasing some crashs.
Fix sql backward rules for makefile
Follow up ea8ccfc82e91efb9fc1be3d3397d538d80101c84
-Update message with Euphy suggestion.
-Add new test case.
-Fix **bugreport:9278** (infinte-warp-1ma-h-cpu-usage-100)
Add gdb check for configure suggestion on bugreport:4645.
Add the missing update in infinite_warp.txt