README examples are out of date

[elmarquez]

README.md examples are not in line with the examples provided here:

https://github.com/codenotary/immudb-client-examples

People who follow these examples will encounter the ImmudbClient is not a function error.

[tomekkolo]

@elmarquez , immudb-node was updated to v2. Examples repository needs to be updated, but you can find a lot of examples in immudb-node repo under https://github.com/codenotary/immudb-node/tree/master/immudb-node-showcase

[elmarquez]

@tomekkolo thank you so much for letting me know