[Fiware-tech-help] [Chp - IoT][IDAS] Explain the meaning of the variables that need to be set

[David Muriel]

Some of the components of the platform need some environment variables
set before installing the required package.  There is no explanation
of what are these variables and what may need to be modified in order
to install the platform.  This variables can be found for:

 * neoidas-monitbd
 * neoidas-bd
 * neoidas-fe
 * neoidas-be