Update README.md

[leaked]

Hi I updated the badges and version

[whatyouhide]

Hey @mohsen-in, thanks for the PR!

However:

• The changes from * to - for lists are not really necessary and mostly create churn. Markdown is going to display them the same and we use them consistently, so we'll stick with *.
• The version requirement ~> 2.0 allows version 2.5.x too, so there's not much need to change it.
• When we can, we try to avoid Hex badges since historically shields.io does a lot of requests and sub-optimal caching.

Thanks anyways and I hope this all made sense! 💟