Update EditorConfig to reduce noise in commits due to whitespace changes

[tristan00b]

Addresses the config part of issue 1008 - Fixing whitespace violations

Changes:

• .editorconfig
  • Preamble updated to reflect current usage
  • Simplified catch-all glob expression
  • Set insert_final_newline = true
  • Set end_of_line = crlf for Windows shell scripts
• .gitattributes
  • Set rules for CMake and Powershell files to lf and crlf, respectively

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oli & alex

[tristan00b]

Changed my mind, I think I'd like to reformulate the issue, which is dealing with whitespace violations. I will create a formal issue and propose my solution.

Reopened after discussion in #1008.