Revert "removed perspective lib ref. from docs since ..."

This reverts commit f6173c0.

Author: RandomFractals

README.md

@@ -8,7 +8,7 @@
 [![Installs](https://vsmarketplacebadge.apphb.com/installs/RandomFractalsInc.vscode-data-preview.svg?color=orange)](https://marketplace.visualstudio.com/items?itemName=RandomFractalsInc.vscode-data-preview)
 [![Downloads](https://vsmarketplacebadge.apphb.com/downloads/RandomFractalsInc.vscode-data-preview.svg?color=orange)](https://marketplace.visualstudio.com/items?itemName=RandomFractalsInc.vscode-data-preview)
 
-[Data Preview 🈸](https://marketplace.visualstudio.com/items?itemName=RandomFractalsInc.vscode-data-preview) extension for importing 📤 viewing 🔎 slicing 🔪 dicing 🎲  charting 📊 & exporting 📥 **large** `.json` array `.arrow` `.avro` data files, `.config` `.env` `.properties` `.ini` `.yml` configurations files, `.csv/.tsv` & `.xlsx/.xlsb` Excel files and `.md` markdown tables.
+[Data Preview 🈸](https://marketplace.visualstudio.com/items?itemName=RandomFractalsInc.vscode-data-preview) extension for importing 📤 viewing 🔎 slicing 🔪 dicing 🎲  charting 📊 & exporting 📥 **large** `.json` array `.arrow` `.avro` data files, `.config` `.env` `.properties` `.ini` `.yml` configurations files, `.csv/.tsv` & `.xlsx/.xlsb` Excel files and `.md` markdown tables with [Perspective](https://perspective.finos.org/) - streaming data analytics WebAssembly library.
 
 ![Data Preview](https://github.com/RandomFractals/vscode-data-preview/blob/master/images/vscode-data-preview.png?raw=true 
 "Data Preview")