non-automatic updates

[dcooley]

#4 was a good idea and worked well on a 'simple' update. But I think it's not quite future-proof-able.

As we have had to make some changes to the fucntions to get it on CRAN (like adding a void argument) and included extra structs / typdefs so they can be exposed

So instead I propose updating the script to

• download the latest upstream h3 source files
• build & make the code, because this generates h3api.h
• remove h3api.h.in
• h3Assert.c needs an typedef int unused; to avoid the "ISO C forbids an empty translation unit [-Wpedantic]" warning
• h3Index.c - h3ToString - remove 'sprintf' line and return return E_FAILED;
• where is version 0.1.1 (the one on CRAN)? - this contains the (void) fixes.
• compare the function definitions of those just downloaded to our existing ones (in h3libapi.h) and output differences in a .txt / log of some sort
• Then we manually compare the differences and decide which ones to keep / disregard / edit
• (and possibly have a build_init.sh which builds the init.c file)