Merge develop into master for release 2.2.0

[hardbyte]

A fairly impressive list of features went in to this release - https://github.com/hardbyte/python-can/milestone/3?closed=1

Please help me edit this PR to make the changelog.

Changelog

Major Features

• Fallback message filtering implemented in Python for interfaces that don't offer better accelerated mechanism. Software filtering of messages #157, Software filtering for all Buses #277, usb2can doesn't implement filters #104
• SocketCAN interfaces have been merged (socketcan_native and socketcan_ctypes), this is now completely transparent for the library user. Merge socketcan_native and socketcan_ctypes into one #326
• automatic detection of available configs/channels in supported interfaces (see Support for automatic configuration detection #303)
• Added synchronized (thread-safe) Bus variant. Feature: Synchronized bus instance #315
• context manager support for the Bus class. Feature: Context manager #283
• added CSVReader. Improved testing of CSVReader/CSVWriter Added CSVReader and CSVReader/CSVWriter tests #270
• Notifier supports multiple buses Improved channel handling #332

Removals

• Dropped support for Python 3.3 (officially reached end-of-life in Sept. 2017)
• Deprecated the old CAN module, please use the newer can entry point (will be removed in version 2.4). old CAN.py #267

Interface Specific Changes

There were many changes and a lot of cleanup effort in the individual interfaces. Some of the highlights:

SocketCAN

• Use socketcan in the future instead of socketcan_native or socketcan_ctypesMerge socketcan_native and socketcan_ctypes into one #326
• Cyclic improvements SocketCAN (native) cyclic improvements #323
• Low level fixesSocketCAN low level fixes #296
• Improved logging SocketCAN low level fixes #296

Vector

• CAN FD support Vector CAN FD #311
• Fix bug where messages were sent to only one virtual channel Messages sent to both Vector virtual CAN channels when specified to be sent to only one channel #302
• Various fixes in Vector improvements #258:
  • Avoid polling by using Win32 events when possible
  • Support for receive_own_messages argument

PCAN

Use configured bitrate. #254

USB2CAN

Show stopping bug #219 has been fixed.

Minor Changes

• Minor api change to the can.Notifier adding add_listener and remove_listener methods can.Notifier enhancements #266
• SqlReader and SqlWriter have been renamed to SqliteReader and SqliteWriter. add a deprecated notice to 'SqlReader' for users #263
• readers/writers now support error frames correctly. CanutilsLogWriter and CanutilsLogReader fail when working with error frame messages #217, Fixing #217 & #218 #247, Support error frame messages in ASCWriter and ASCReader. #256
• bug fixes
• a lot of (CI) testing effort. Feature travis to build sphinx docs #342
• improved documentation
• code cleanup. cleanups,fixes & docs in Bus.__new__() and util.load_config() #309

Try it out from PyPi:

pip install python-can==2.2.0-rc.1 

[felixdivo]

How do we list the changes in the individual interfaces? There are changes that might be interesting for some, like setting bitrate was added and alike.

[felixdivo]

Looks good 👍

[felixdivo]

Hey @hardbyte, shouldn't successful AppVeyor tests also be required to be able to merge into master?