Let's drop Python 3.3 & 3.4 support

[asvetlov]

Python 3.3 is too old and not maintained anymore.
I doubt if anybody runs aioredis on this version.

Honestly it's time to drop 3.4 too -- the next aiohttp release most likely will support python 3.5+ only.

[hugovk]

The numbers support this.

Here's the pip installs for aioredis from PyPI for the last month:

$ pypinfo --percent --pip aioredis pyversion
python_version percent download_count
-------------- ------- --------------
3.5              62.8%         16,277
3.6              35.7%          9,250
3.4               0.6%            152
2.7               0.5%            135
3.7               0.3%             73
3.3               0.1%             25
2.6               0.0%              1

[popravich]

Lets drop 3.4 as well

[asvetlov]

BTW Next aiohttp release will be limited to Python 3.5.3+

[popravich]

TODO:

• replace old-style @asyncio.coroutine with async def;
• update tests;
• rename py35_* tests;
• drop old py34 examples

[popravich]

Done.