Fixed a bug in the sendrecv method when using multi-threading

Improve Pcap & PcapNg support (particularly timestamps)

Add & test DNS over TCP, update dnstypes

[Layers] Added fields desc on CookedLinux + L3pcapsocket

- Added fields on CookedLinux
- Tiny tiny tiny fix: added description to L3pcapsocket

Fix tiny bugs

* Add conf.checkIPinIP

This setting, when set to False, will exclude IP layers which encapsulate
another IP layer from the checks to tell if a packet is an answer to
another one.

Fixes #383

* conf.checkIPinIP affects both IP() and IPv6()

Setting conf.checkIPinIP will handle IP()/IP(), IP()/IPv6(),
IPv6()/IP(), IPv6()/IPv6().

Thanks @guedou!

* Clean-up IP.hashret and .answers code

* Add tests for .hashret() and .answers()

* Support (BPF) filter in sniff() with offline parameter set

Fixes #393
Also, fixes #355

* Add tests for wrpcap() and sniff(offline=)

as suggested by Guillaume.

Also, cleanup regression.uts since it was a pain to find a place
to add those tests.

* Fix PATH for tcpdump with non-root user

* Do not run tcpdump tests when tcpdump is not available

* Appveyor tests: install WinDump.exe

Thanks @gpotter2

Added roadmap link

* [isis.py] Add support for some SubTLVs
* [isis.py, isis.uts] Fix, (unit-)test and extend SubTLVs support

Fixed the invalid copy_flag in some ip options

HTTP/2 support

Add AppVeyor badge

AppVeyor support

fix version when installing from git archive

[bug] fix issue with python-pcapy interface next() function 

[Windows] Fix autocompletion crash

[bug] fix issue with python-pcapy interface next() function not properly catching if next packet does not exist.