update docs

Author: lsgrep

README.md

@@ -18,12 +18,11 @@ Checkout the [Releases](https://github.com/lsgrep/mldocs/releases), download the
 then double click it(You have to have Alfred + Powerpack License).
 
 ## Conventions
-For convenience, a few prefixes are automatically expanded. 
+For convenience, a few prefixes are automatically expanded(see [PR](https://github.com/lsgrep/mldocs/compare/expand-conventions?expand=1) for more).
 - `np` => `numpy`
 - `pd` => `pandas`
 - `plt` => `pyplot`
 - `sns` => `seaborn`
-```
 
 ## How does it work
 - `mldocs` fetches the doc data from Github(`data/ml.json`), then caches the data for a few days