Release 2.1.35

[jsirois]

On the docket:

• Ensure venv pex does not enter a re-exec loop. Ensure venv pex does not enter a re-exec loop. #1286
• Improve resolve error information. Improve resolve error information. #1287
• Expose Pex tools via a pex-tools console script. Expose Pex tools via a pex-tools console script. #1279
• Fix auto-created --venv core scripts. (Fix auto-created --venv core scripts. #1278)

[jsirois]

Moved from Release 2.1.34 in #1263 to make way for a hotfix for #1267.