Improve R.exe exit code error handling

[stubartmess]

A common problem with the R tool is that it outputs "False Errors" like the following: "The R.exe exit code (4294967295) indicted an error"

I call this a false error because data passes out of the R script the same as if there were no error. As such, this error can generally be ignored. In my use case, however, my R tool is embedded within an iterative macro, and the error causes the iterator to stop running.

I was able to create a workaround by moving the R tool to a separate workflow and calling it from the CReW runner macro within my iterator, effectively suppressing the error message, but this solution is a bit clumsy, requires unnecessary read/writes, and uses nonstandard macros.

I propose the solution suggested by @mbarone (https://community.alteryx.com/t5/Alteryx-Designer-Discussions/Boosted-Model-Error/td-p/5509) to only generate an error when the R return code is 1, indicating a true error, and to either ignore these false errors or pass them as warnings. This will allow R scripts and R-based tools to be embedded within iterative macros without breaking.