v0.4: Add introductory section and breast cancer records

Added

The intro has been migrated from the original project description submitted to ΔTissue.

Datatables support has also been added to the tables under Data resources.

The clincal_patient_brca.txt file has been added to to the tables under Data resources.

An embedded representation of the TNBC pathway, https://www.wikipathways.org/index.php/Pathway:WP5211.