use MethodHandles instead of reflect.Method

[pjfanning]

jackson-databind is very dependent on java reflection but we can start rewriting some pieces of code to avoid it

[yawkat]

can these be static final fields? those have special optimizations in hotspot

[pjfanning]

can these be static final fields? those have special optimizations in hotspot

they can't be static final the way the code is written at the moment but a bigger rewrite might be able to achieve that

it looks like we won't be able to merge this anyway because animal-sniffer (Android compatibility checking) is rejecting the use of MethodHandles