P26, P29, P61, P62, P64, P66, P74, P75, P86, P87, P88, P93, P95, P98, P105, P109, P115, P119, P122, P125, P151, P155, P169, P203, P271, P280, P303, P407, P425, P451: Replaced explicit generic types in Java solutions with diamond operator.
Readme: Updated Java SE version requirement from 5 to 7.