Add a simple system for table diffing to ODK

[matentzn]

Daff is an amazing framework for diffing tables: https://github.com/paulfitz/daff

pip install daff
daff --input-format tsv m1.sssom.tsv m2.ols.sssom.tsv > diff.tsv
daff render  --input-format tsv diff.tsv > diff.html   

Gives us a nicely rendered diff of the table, e.g

We can then use pandoc to generate GitHub flavoured markdown:

pandoc -s diff.html -o diff.md -t gfm 

While colouring cell content directly is not supported in GitHub flavoured markdown, we could inject emojis into the changed cells by using replace in the --> character:

This generates a table like

@@	subject_id	subject_label	predicate_id	object_id	mapping_justification	...
...	...	...	...	...	...	...
	ZFA:0000012	central nervous system	oio:hasDbXref	TAO:0000012	semapv:UnspecifiedMatching	...
→	ZFA:0000013	cranial ganglion	oio:hasDbXref	TAO:0000013:warning:→:warning:	semapv:UnspecifiedMatching	...
	ZFA:0000014	dorsal aorta	oio:hasDbXref	TAO:0000014	semapv:UnspecifiedMatching	...
...	...	...	...	...	...	...
	ZFA:0000019	epiphysis	oio:hasDbXref	TAO:0000019	semapv:UnspecifiedMatching	...
→	ZFA:0000020	extraembryonic structure:warning:→:warning:extrembryonic structure	oio:hasDbXref	TAO:0000020	semapv:UnspecifiedMatching	...
	ZFA:0000020	extraembryonic structure	oio:hasDbXref	CARO:0000042	semapv:UnspecifiedMatching	...
...	...	...	...	...	...	...