增加玩家的磁力强度增加和衰减，  PLAYER_MH_INCREASE_FACTOR
增加玩家的磁力中心偏移，   PLAYER_MAGNET_OFFSET
增加玩家和炸弹之间的磁力不对等  PLAYER_ITEM_MAGNETIC_FACTOR

Signed-off-by: hunterhbb <hunterhbb@gmail.com>
Merge branch 'develop' of https://github.com/pandamicro/Magnetic-Force.git into develop
Merge branch 'develop' of https://github.com/pandamicro/Magnetic-Force.git into develop
适配金堂的推进力

Signed-off-by: hunterhbb <hunterhbb@gmail.com>