Update JSON files
Split git repo discovery into separate script

This step runs on the bootstrap machine where a git repo is present.
Everything else runs on the generator machine, where we can build
the required binaries.
Use WRKDIR environment variable
Need core to invoke cf-promises
Remove generated files
Generate files in _generated, get rid of _json
Delay reading of syntax map until we have it.
Make sure directories exist before writing to them
Generated within the generator...
Better log message when code could not be included
File names are now absolute
Generate help files as well, and simplify a bit
Remove help files for core binaries

Generated on the fly now. Leave cf-hub, which needs to be
maintained manually.
Don't generate version-specific library files.

Only one version is documented in any branch anyway.
Don't escape here
Update README

Point to the correct files, remove some information that is redundant.
Move publishing steps into a script