improve README with visualizations & emojis

[sreichl]

• add materials from my presentations (Comp CeMMies, FS,…) on MR.PARETO where useful
  • video recording: no
  • whole presentation: after cleanup (ie removal of confidential content) go ahead
  • individual slides: can/should I use some of the slides in the repository as it helps with explanations? → yes
• [x] add emojis (inspiration: https://github.com/franciscozorrilla/metaGEM)
  • [x] all sections of this README
  • [x] template and all module READMEs (always the same)
• [x] callout box for starring
• [x] repo activity, lines of code, stargazer plot #10
• [x] #9

Modules

• [x] Unsupervised Analysis
• [x] Split, Filter, Normalize and Integrate Sequencing Data
• [x] Differential Analysis Using limma
• [x] Enrichment Analysis
• [x] Genome Track Visualization
• [x] scRNA-seq Processing using Seurat
• [x] Differential Analysis using Seurat
• [x] Perturbation Analysis using Mixscape from Seurat
• [x] ATAC-seq Processing