pipelinedb is not implemented in Python -> removing

Created by: sfermigier

README.md

@@ -375,7 +375,6 @@ Inspired by [awesome-php](https://github.com/ziadoz/awesome-php).
 *Databases implemented in Python.*
 
 * [pickleDB](https://pythonhosted.org/pickleDB/) - A simple and lightweight key-value store for Python.
-* [PipelineDB](https://www.pipelinedb.com/) - The Streaming SQL Database.
 * [TinyDB](https://github.com/msiemens/tinydb) - A tiny, document-oriented database.
 * [ZODB](http://www.zodb.org/en/latest/) - A native object database for Python. A key-value and object graph database.