SFD v2.37 update

SFD patch notes.

18-08-24 Ver 2.37

* Game changes
- Simple tutorial screens added.
- Simple Rankings added. (More detailed rankings will be implemented later)

* Bug fixes
- 'Undead revived where cannot be atttacked' bug fixed.
- Room generating algorithm is changed. Now inaccessible position(Where cannot be reached by walking) is not generated.
- 'Character information window appears and cannot proceed when allies are all stunned' bug fixed.

18-08-16 Ver 2.36
* Game changes
- Added sprites of 7'th floor boss Raeleus 
- Minor UI and sprites changes.

* Bug fixes
- 'Crash when attacking flame trap bug' fixed. Now most of melee attack cannot hit undestractible obstacles.
- Removed closed button of 'Hero level up window'.