Phoenix-letter

Changes
- Adds python 3.11 to GitHub Actions as an optional step


Updates dependencies:
- Bump `boto3` from 1.20.52 to 1.26.32

Update test and dev dependencies:
- Bump `moto` from 2.2.2 to 4.0.12
- Bump `isort` from 5.9.3 to 5.10.1
- Bump `coverage-badge` from 1.0.1 to 1.1.0.
- Bump `setuptools` from 60.8.2 to 65.6.3
- Bump `coverate` from 6.3.1 to 7.0.0

Changes
- Adds python 3.10 support
- Removes Travis CI from the repository
- Added Github Actions to handle build and testing


Updates dependencies:
- Bump boto3 from 1.18.21 to 1.20.52
- Bump coverage from 5.5 to 6.3
- Bump coverage from 6.3 to 6.3.1
- Bump twine from 3.4.2 to 3.8.0
- Bump setuptools from 57.4.0 to 60.8.2

Adds support for SQS FIFO queues (16)

Updates dependencies.

- boto3: 1.16.51 -> 1.18.21

Test:
- moto: 1.3.16 -> 2.2.2
- mock: 4.0.2 -> 4.0.3
- coverage: 5.3.1 -> 5.5
- isort: 5.7.0 -> 5.9.3
- black: 21.7b0 -> 20.8b1

Dev:
- setuptools: 51.1.2 -> 57.4.0
- twine: 3.3.0 -> 3.4.2

Changes:
- Update all requirements libs to a latest compatible version
- Update README with new parameters and PyPi badge and link
- Removal of `nosetest` due to the lack of updates (_replaced with `unittest`+ `coverage`_)
- Due to an issue with Moto compatibility with `Mock` library, `mock` version is fixed at 4.02 [spulec/moto3535]
- Removed use of assert deprecated function `assertEquals`
- Removed Python2 import conditions and `six` from requirements

Changes
* Adds Black and isort checks to TravisCI
* Removes support to deprecated python versions: **2.7, 3.5, 3.6**
* Adds support to Python 3.9
* Adds PyPi information on README

Changes introduced in previous pre-releases ([v0.3.1b](https://github.com/renanvieira/phoenix-letter/releases/tag/v0.3.1b)):
* Now Phoenix Letter is able to handle messages with no MessageAttributes. (kudos to WafflesMcDuff for the PR!)Updated libs
* Improved test coverage