update java version
P87: Monopoly odds
P88: Product-sum numbers
P91: Right triangles with integer coordinates
P90: Cube digit pairs
Merge branch 'master' of https://github.com/taoyijie/ProjectEuler.git

Conflicts:
	src/level4/P91.java
P93, 94, 95
P98
P101: Optimum polynomial
P102, 104, 105
P105, 106
P107
108, 110
test