----------------
- Drop support for Python 2.6, 3.2 and 3.3 PR 300
- add the missing read_binary_values and read_ascii_values (PR 301)
- deprecate old methods in MessageBased (ask, read_values, query_values,
write_values, ask_delay) (PR 301)
- add support for hp headers in binary data (PR 301)
- fix encoding issue in write_ascii_values (PR 301)
- use import to load backend rather than pkgutil.iter_modules. This allows
PyVISA to support PyInstaller PR 307
- improvements to the visa shell: attributes type conversion (PR 299),
termchar command (PR 285), timeout command (PR 284),
support for non-default backend (PR 283), console script pyvisa-shell
(PR 286)
- improve speed for large data transfer by using bytearray instead of bytes
(PR 282)
- make Resource a context manager closing it. (PR 255)
- add 64 bits version of registry based functions (PR 278)
- make exceptions pickable (PR 249)
- add resource_name to the output of parse_resource_extended (PR 238)
- fix wait_on_event behavior in case of timeout (PR 234)
- allow selecting the backend using the PYVISA_LIBRARY env var (PR 195)