[PR/Issue templates] normalize, group, sort + add myself for deepspeed
This PR:
* case-normalizes, groups and sorts the tagging entries
* removes one duplicate
* adds myself for deepspeed
* adds/removes/moves others based on their suggestions through this PR

@LysandreJik, @sgugger, @patrickvonplaten 

Once the PR template is complete and everybody is happy I will sync with the Issue template. So please only review the former if you're just joining in.<|||||>should we add bullets? As in:

```

Models:

- albert, bert, xlm: @LysandreJik
- blenderbot, bart, marian, pegasus, encoderdecoder, longformer, reformer, t5, transfoxl, xlnet: @patrickvonplaten
- fsmt: @stas00
- funnel: @sgugger
- gpt2: @patrickvonplaten, @LysandreJik
- rag: @patrickvonplaten, @lhoestq
- tensorflow: @jplu

Library:

- benchmarks: @patrickvonplaten
- deepspeed: @stas00
- ray/raytune: @richardliaw, @amogkam
- text generation: @patrickvonplaten
- tokenizers: @n1t0
- trainer: @sgugger

Documentation: @sgugger

HF projects:

- nlp datasets: [different repo](https://github.com/huggingface/nlp)
- rust tokenizers: [different repo](https://github.com/huggingface/tokenizers)

Examples:

- maintained examples (not research project or legacy): @sgugger, @patil-suraj
- research_projects/bert-loses-patience: @JetRunner
- research_projects/distillation: @VictorSanh
```<|||||>I like bullets.<|||||>someone to tag for ONNX issues? @mfuntowicz?