Backport fix to prune the trie from zmq3.

Signed-off-by: Staffan Gimåker <staffan@spotify.com>
Change peer_identity_size (in all cases) in the command_t structure to be a size_t instead of an unsigned char.

The peer_identity_size field in the attach and bind substructure is
used to generate a C++ base_string object from an unsigned char *, and
that object expects a size_t, not an unsigned char.  If an unsigned
char is used, the HPUX aCC compiler gets confused and can't figure out
which constructor to use.

Signed-off-by: AJ Lewis <aj.lewis@quantum.com>
clarifying installation documentation for users building from repo
Patch from Mikko Koppanen for #LIBZMQ-301

Add the '-Ae' flag when using aCC

Check if CLOCK_MONOTONIC defined before using it - if not, use gethrtime()

Signed-off-by: AJ Lewis <aj.lewis@quantum.com>
Fix segfault bug when pruning the trie.

Signed-off-by: Staffan Gimåker <staffan@spotify.com>
Fix bad combination of gcc3, -Werror and private destructor.
Fix basic_string<unsigned char> not implemented in stdc++ 3
Source char_traits<unsigned char> from GCC C++ Library directly to clarify license.

http://gcc.gnu.org/onlinedocs/libstdc++/
Previously borrowed code from id3lib was considered shady.
Placed in its own file for style reasons.
Fix: runtime patch for when system has clock_gettime but does not support CLOCK_MONOTONIC.
Fix: Whitespace and comment.
Backport ./configure --with-poller from libzmq development.

If you've been configuring the poller using:
CPPFLAGS=-DZMQ_FORCE_POLL ./configure

Now you're going to want to say:
./configure --with-poller=poll
Prevent unused variable warning in presence of assertions.
Merge pull request #41 from thesamet/master

Prevent unused variable warning in presence of assertions.
Merge pull request #39 from vortechs2000/issue-301

Fix builds on HP-UX 11iv3 when using either gcc or aCC
Prepared for 2.1.12
Updated NEWS for PR #39
Merge pull request #36 from gimaker/trie-pruning

Backport fix to prune the trie from zmq3 (LIBZMQ-305)
Merge pull request #38 from jtzl/master

updated INSTALL documentation as per pull request #37
Merge pull request #40 from gitfoxi/master

Backport some build fixes for old-ass Linux from libzmq development.
Add algorithm include for std::swap