Update pyproj to >3.0.0 and reformat setup.py with PEP-8 guide.

[lionlai1989]

Description

This PR is about solving this issue, ie, updating pyproj>3.0.0.

Type of change

The changes of this PR are:

• [x] Update pyproj>3.0.0 in setup.py.

  requirements = [
  "numpy",
  "scipy",
  "rasterio[s3]>=1.2a1",
  "utm",
  "pyproj>3.0.0",
  "beautifulsoup4[lxml]",
  "plyfile",
  "plyflatten>=0.2.0",
  "ransac",
  "rpcm>=1.4.6",
  "srtm4>=1.1.2",
  "requests",
  ]

• [x] Reformat setup.py following PEP-8 guide.

How Has This Been Tested?

This project has been tested with the command, pytest tests/, and only 1 test fails.

======================================= 1 failed, 32 passed, 4 warnings in 148.84s (0:02:28) ========================================

The tests/end2end_test.py failed and the error is not coming from s2p but from the srtm4 package. In s2p, it downloads SRTM data from https://srtm.csi.cgiar.org/, but the SSL certificated has been expired (check https://github.com/centreborelli/srtm4/issues/16). Thus the failing test occurs.
The error:

E               requests.exceptions.SSLError: HTTPSConnectionPool(host='srtm.csi.cgiar.org', port=443): Max retries exceeded with url: /wp-content/uploads/files/srtm_5x5/TIFF/srtm_48_17.zip (Caused by SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: certificate has expired (_ssl.c:1131)')))

The error is not from either s2p or srtm4 package but from the website.

Checklist:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] My changes generate no new warnings
• [] Existing unit tests pass locally with my changes

[kidanger]

s2p uses pyproj>=3 since #137 was merged. This PR can be closed