Update build_component.py

[karthikgvss]

Added proper error message with link to build instructions.

[vladimir-v-diaz]

You might want to raise an exception here, or call sys.exit(1) (similar to help_exit()'s approach.

[vladimir-v-diaz]

The official Python tutorial has a section on exceptions. One approach you may follow here is to log/print information about the requiredscripts/config_build.txt file, and then re-raise the exception with a bare raise (to avoid masking the original exception).

The following article explains why exceptions can lead to cleaner code:
Write Cleaner Python: Use Exceptions

[karthikgvss]

I am checking if build config exists before creating RUNNABLE directory. This resolves #14 . I am also printing better message resolving #13. Please suggest.