Merge pull request #602 from hintjens/master

Some logging fixes / additions
Fix MSVC build breaks.
Change ULL suffix to LLU for portability to MSVC2010/2012.
Make explicit lossy numeric cast.
Add missing comma and try again.
Merge pull request #604 from evoskuil/master

Fixes MSVC build breaks.
Create new class for doubly linked lists.
Merge pull request #600 from Q-Leap-Networks/pull-zdlist

Create new class for doubly linked lists.
Merge pull request #606 from hintjens/master

New code wasn't working with ZMQ v2
zdlist: Indentation: convert tabs to 8 chars
zdlist: add spaces before (
zdlist: blank line before method declaration
Merge pull request #607 from Q-Leap-Networks/pull-zdlist-style-fix

coding style fixes for zdlist
Added zdlist man page

Hint: "./mkman zdlist" in doc directory creates or updates one man page.
To update all existing man pages, "./mkmans".