Setup boilerplate

[FYJen]

This PR bootstraps the framework for the SDK. The goal is to maintain the similar interface for all of our admin SDKs (starting with nodejs - https://docs.magic.link/admin-sdk/node-js)

The example below:

pip install magic-admin

from magic_admin import Magic

magic = Magic('secret_key')

# Examples for Token
magic.Token.get_issuer()
magic.Token.get_public_address()
magic.Token.decode()
magic.Token.validate()

# Examples for User
magic.User.logout_by_issuer()
magic.User.logout_by_public_address()
magic.User.logout_by_token()
magic.User.get_metadata_by_issuer()
magic.User.get_metadata_by_token()
...

The tests and pre-commit hook have been set up already. Package has been tested with

platform darwin -- Python 3.6.5, pytest-5.4.1, py-1.8.1, pluggy-0.13.1
rootdir: /Users/ajen/pg/magic-sdk-python
plugins: web3-5.4.0, cov-2.8.1
collected 4 items

tests/unit/magic_test.py .                                                                                                                                                                                                                                             [ 25%]
tests/unit/resources/api_test.py .                                                                                                                                                                                                                                     [ 50%]
tests/unit/resources/token_test.py .                                                                                                                                                                                                                                   [ 75%]
tests/unit/resources/user_test.py .                                                                                                                                                                                                                                    [100%]

---------- coverage: platform darwin, python 3.6.5-final-0 -----------
Name                              Stmts   Miss  Cover   Missing
---------------------------------------------------------------
magic_sdk/__init__.py                 1      0   100%
magic_sdk/magic.py                    2      0   100%
magic_sdk/resources/__init__.py       2      0   100%
magic_sdk/resources/api.py            2      0   100%
magic_sdk/resources/token.py          2      0   100%
magic_sdk/resources/user.py           2      0   100%
magic_sdk/utils/__init__.py           0      0   100%
magic_sdk/utils/http.py               0      0   100%
magic_sdk/utils/time.py               0      0   100%
---------------------------------------------------------------
TOTAL                                11      0   100%


========================================================================================================================= slowest 10 test durations ==========================================================================================================================

(0.00 durations hidden.  Use -vv to show these durations.)
============================================================================================================================= 4 passed in 0.07s ==============================================================================================================================
py36 runtests: commands[4] | pre-commit install -f --install-hooks
pre-commit installed at .git/hooks/pre-commit
py36 runtests: commands[5] | pre-commit run --all-files
Flake8...................................................................Passed
Trim Trailing Whitespace.................................................Passed
Fix End of Files.........................................................Passed
Check for merge conflicts................................................Passed
Fix requirements.txt.....................................................Passed
Tests should end in _test.py.............................................Passed
Fix double quoted strings................................................Passed
Forbid new submodules....................................................Passed
Check Yaml...............................................................Passed
Check JSON...........................................(no files to check)Skipped
autopep8.................................................................Passed
Add trailing commas......................................................Passed
Reorder python imports...................................................Passed
pyupgrade................................................................Passed
__________________________________________________________________________________________________________________________________ summary ___________________________________________________________________________________________________________________________________
  py36: commands succeeded
  congratulations :)