Add unsafe signatures for Java 8, review Java 7

[GoogleCodeExporter]

Currently Java 7 and Java 8 unsafe signatures are just copies of Java 6.

We should check especially Java 8 for new method signatures that use default 
charset, default locale, and default timezone. Java 7 is unlikely that new ones 
are introduced, but Java 8 has many new ones (because of introduction of 
closures).

Original issue reported on code.google.com by uwe.h.schindler on 9 Nov 2013 at 11:29