Lint TODO - ignore editor files

[ewels]

Use fnmatch to properly apply glob expressions found in the .gitignore file when searching all pipeline files for TODO strings.

Closes #477

PR checklist

• This comment contains a description of changes (with reason)
• If you've fixed a bug or added code that should be tested, add tests!
• Documentation in docs is updated
• CHANGELOG.md is updated
• README.md is updated

[codecov]

Codecov Report

Merging #689 into dev will decrease coverage by 0.06%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##              dev     #689      +/-   ##
==========================================
- Coverage   81.41%   81.35%   -0.07%     
==========================================
  Files          13       13              
  Lines        2696     2676      -20     
==========================================
- Hits         2195     2177      -18     
+ Misses        501      499       -2     

Impacted Files	Coverage Δ
nf_core/lint.py	91.91% <100.00%> (+0.30%)	⬆️
nf_core/__main__.py	62.08% <0.00%> (-2.79%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 02593c5...b3c9ce4. Read the comment docs.