Add notice as to which version of Jina examples work with.

[FionnD]

Feature request:
A notice should be added to the top of all the READMEs in the example repo specifying which version of Jina these examples work with. The following text snippet is a good suggestion for what to add.

⚠️ Please note that examples currently only work with Jina version 1.1. Please make sure you are running this version when using the examples. pip install jina == 1.1

[rutujasurve94]

Working on wikipedia, cross modal, multi modal, object search tumblr examples to update the latest version compatibility.