Use native windows APIs for File.exists()

On windows, there are obscure cases where _wstat can return non-zero for a path that
actually exists, but the native GetFileAttributes returns valid attributes.  This is
the case in particular when the user or process doesn't have permissions to access
the directory (for instance, anything outside of %temp%\Low, when running as a
low-integrity process).

This was causing problems with .mkdirs() - which first tries to check if the parent
exists, and creates it if it doesn't. In our particular case, the exists() was
returning false for the parent, even though it exists, and .mkdir() works fine,
mkdirs() fails for the same directory.
force unicode support in java-io.cpp when including windows.h
fix linux->darwin cross-compile

There were two issues: the linux->darwin cross compiler is more stringent
about unused variables, and the makefile specified flags for building ON
darwin that were actually applicable whenever we are building FOR darwin.
JVM_GetDeclaredClasses and JVM_GetClassInterfaces should return instances of Class[], not Object[]
FIX : To run embeded application, it complains for missing libgcc_s_dw2-1.dll and libstdc++-6.dll.(#60)
Expanded DatagramChannel and corrected blocking configuration in connect().
tweaks to prepare for 0.7 release
update copyright years

Previously, I used a shell script to extract modification date ranges
from the Git history, but that was complicated and unreliable, so now
every file just gets the same year range in its copyright header.  If
someone needs to know when a specific file was modified and by whom,
they can look at the Git history themselves; no need to include it
redundantly in the header.
fix Clang warnings
fix Android classpath build

Hopefully it will stay fixed this time, since we now specify commit
hashes for each dependency which are known to work.
adding zipentry and zipoutputstream classes
only use librt on Linux; OS X doesn't have or need it
updating zipentry
add zipOutputStream and change DeflaterOutputStream
Add tests for creating zip files using both write methods
fixing problems!
zipentry test
Added native Math.exp() implementation.
Merge remote-tracking branch 'jet/master'
Adding another possible case for addThread to expect. One common case that triggers is is when both arguments to addThread are the same thread (such as the call from attachThread). SWT on darwin seems to do this for dialog boxes.