* Added another difficulty option for Boss Rush mode
* Added higher difficulty options for Boss Rush mode:
D: Fight all enemies consecutively
C: + Garbage doubled
B: + Deathbombing time shortened
A: + Enemies must be defeated within time limit
S: + Enemies have invincibility time
U: + Enemies clear your Power
X: + Spell cards clear your Power
* Added another difficulty for Cirno and Flandre
* Disable BOMB during invincibility periods
* Pause lock timer during invincibility periods in Stack mode
* Clear one garbage line when break a spell card in Shoot mode