DOCS: Add front page cards for supported and external model implement… #1075

Job	Run time
linux-64-py	5m 49s
macOS	8m 32s
win-64	9m 11s
random_seed_generation_test	3m 51s
Standard 1-Zone Example (MTC)	50m 45s
Standard 2-Zone Example (SANDAG)	1h 33m 47s
prototype_mtc	56m 8s
Estimation Mode Unit Tests	26m 19s
Expression Profiling Tests	8m 36s
prototype_mtc_extended	1h 28m 40s
prototype_marin	1m 55s
placeholder_psrc	55m 37s
production_semcog	6m 41s
placeholder_multiple_zone	10m 27s
estimation_edb_creation_test	6m 53s
Estimation Notebooks Test	49m 51s
prototype_sandag_xborder	5m 51s
prototype_mwcog	1h 0m 36s
develop-docbuild	2m 51s
	9h 12m 20s

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