Update xlib.nim

remove -d:MACROS requirement for xlib shortcut functions
Update xutil.nim
Update glx.nim

glx attributes should be int32
Update xutil.nim

removed converter
Update keysym.nim

properly type all the keysyms
Add DragonFly as essentially a clone of FreeBSD
Fixed async send in ftpclient module.
Exposed process file handles in osproc module.

The file handles of a PProcess instance can now be accessed through
the inputHandle(), outputHandle(), and errorHandle() methods.

Also tidied up documentation for stream accessor procs a bit.
Add compressBound proc to zlib wrapper.
Added a TSocketHandle type to winlean.nim and posix.nim

Edited sockets.nim and asyncio.nim to use the new TSocketHandle type.
Merge pull request #624 from Varriount/win64/fix-sockets

Added a TSocketHandle type to winlean.nim and posix.nim
Merge pull request #622 from rbehrends/master

Exposed process file handles in osproc module.
Merge pull request #615 from fowlmouth/patch-10

Update xlib.nim
Merge pull request #617 from markuspf/master

Add DragonFly as essentially a clone of FreeBSD
Fixed regression on ARM caused by the changed behaviour of noStackFrame in commit 725dab4bedd.
Fixed definition of seqShallowFlag.
Added an insertion function that inserts elements of an openarray.

Added a deletion function that allows elements between two positions in a sequence to be deleted
Added instructions on using koch to compile nimrod with GDB support.
Added some information on sequences.
fix for Issue #626 - Distinct and generics not working together