Create examples for usage of the library

[ESapenaVentura]

Create examples for:

• [x] Submitting a sample to BioSamples from an input source (General flow) (No validation)
• [x] Submitting a sample to BioSamples with validation (Checklist) from an input source
• [x] Processing a sample modifying the input (transform function)
• [x] Retrieving a sample from BioSamples using a text search and an attribute search
• [x] Retrieving a sample from BioSamples using an accession
• [x] Updating an existing sample
• [x] Outputting a list of samples to a tsv/excel file

In the form of:

• Jupyter Notebooks
• Python scripts