Re-add mention of discoraged proj keys

Heads-up @Nowosad

Add s2 note, close geocompx#748

Fix typo in sf-dev yaml

update dockerfile

delete unnecessary folder specification 
heads-up @Robinlovelace and see issue geocompx#435

cleans

returns to the proper settings

Merge pull request geocompx#357 from Robinlovelace/revert-356-copyedi…

…t_c14

Revert "Copyedit c14"

readme update

Demonstrate function creation

Should also fix travis.

@Nowosad and @jannes-m, seem like a good direction of (triangular) travel for c12?

one comments

Former-commit-id: ba73266
Former-commit-id: 832edf0