string_asprintf = robust_snprintf + string_wrap
Remove the program config version number

It'll be much easier to deal with future program config format changes
on a per option basis.
Get rid of error code API_E_MALFORMED_PROGRAM_CONFIG

There is no point in having this error code. The user/brickv can do
nothing about it. It's much better to just use default values in case
the values are missing or malformed in the program config on disk.
Improve some process object error messages
Make stdio redirection file names relative to <home>/programs/<identifier>/bin
Move final phase changes to more appropriate places
Properly handle stdio redirection file names in program_scheduler_update