Remove vendored version of requests in botocore and bump version

[kevchentw]

Description of Change

New version of botocore remove vendored version of requests, therefore it should remove all code using botocore.vendored.requests.

I copied the CaseInsensitiveDict from requests to aiobotocore to use this structures. The alternative way it to put requests into requirements, however aiobotocore didn't use other reqeusts function, so I think it is unnecessary.

To reproduces this bug, update botocore to >= 1.13.0, and make requuests with aiobotobore.
The following error will generated.

from botocore.vendored.requests.structures import CaseInsensitiveDict
ModuleNotFoundError: No module named 'botocore.vendored.requests.structures'

ref:

• https://aws.amazon.com/blogs/developer/removing-the-vendored-version-of-requests-from-botocore/
• Remove vendored version of requests boto/botocore#1829

bump version

1. botocore==1.12.252 -> botocore==1.13.2
2. boto3==1.9.252 -> boto3==1.10.2
3. awscli==1.16.262 -> awscli==1.16.266

Assumptions

Checklist for All Submissions

• I have added change info to CHANGES.txt
  • [V ] Detailed description of issue
  • [V ] Alternative methods considered (if any)
  • How issue is being resolved
  • How issue can be reproduced

Checklist when updating botocore and/or aiohttp versions

• I have read and followed CONTRIBUTING.rst
• I have updated test_patches.py where/if appropriate (also check if no changes necessary)
• I have ensured that the awscli/boto3 versions match the updated botocore version

[lgtm-com]

This pull request introduces 2 alerts when merging 5eb29ce into 957c91b - view on LGTM.com

new alerts:

• 1 for Wrong number of arguments in a call
• 1 for Wrong number of arguments in a class instantiation

[lgtm-com]

This pull request introduces 5 alerts when merging 074e088 into 957c91b - view on LGTM.com

new alerts:

• 3 for __eq__ not overridden when adding attributes
• 1 for Wrong number of arguments in a call
• 1 for Wrong number of arguments in a class instantiation

[thehesiod]

cool, thank you! however we should do what botocore is doing and not copy code from them. Also, while working on #659 I found that somehow we missed a bunch of changes to make use match botocore, so we should pull those as well when bumping botocore base version. Thanks for your help!

[thehesiod]

closing in favor of #743 as we shouldn't need to copy the case insensitive dict as that PR shows.