Use direct Apache V2 license URL
Merge pull request #351 from dantran/master

Use direct Apache V2 license URL
Added jnacontrib.x11.api.X.Window.getSubwindows and fixed jnacontrib.x11.api.X.Window.getXXXProperty, returns null if the window property is not found.
Pulled varargs test out of the loop to avoid checking on each parameter

The Method#isVarargs method is now referenced statically to avoid costs
of looking it up on each native method call with at least one parameter.
This also can save a lot of memory, since on every Class#getMethod()
call a new Method object is returned.

Added null check

uses the double-checked locking to speed up subsequent calls to the same
function.

Made Function$Handler$FunctionInfo immutable class to make double check
locking work correctly.

Added description of changes to CHANGES.md
fall back to short names only if long names fail (identified in #243)
update native win32-x86
Folded up the logic for the if statement 

This is a minor code style fix for the method "FAILED" [removed 3 lines and simplified the statement]
update w64 native
Merge pull request #356 from monksy/patch-3

Folded up the logic for the if statement
Added Kernel32#SetSystemTime.
Pointer.getWideStringArray respects the length parameter
Merge pull request #361 from csoren/widestring

Pointer.getWideStringArray respects the length parameter
Passing method and parameter types from Library$Handler#invoke to
Function#invoke. This saves costs for map and reflection lookups.