Make `MAX_BIG_NUMBER` consistent across API v3 models

[rathod-b]

Note: for support questions and enhancement suggestions please use the REopt Forum (under development). This repository's issues are reserved for feature requests and bug reports.

• I'm submitting a ...

  • bug report
  • feature request
  • support request => Please do not submit support request here, see note at the top of this template.

• Do you want to request a feature or report a bug?
  At present, the MAX_BIG_NUMBER is not consistent across API v3 Django data models. The value should either be 1.0e8 or 1.0e9, or we should have multiple max values.

• What is the current behavior?
  MAX_BIG_NUMBER is not used in some places because its not consistent with maximum possible value in REopt.jl.

• If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem via
  https://plnkr.co or similar (you can use this template as a starting point: http://plnkr.co/edit/tpl:AvJOMERrnz94ekVua0u5).
  Open models.py in reoptjl app and compare MAX_BIG_NUMBER with the maximum values required in various models.

• What is the expected behavior?
  All maximum values in Django models are either MAX_BIG_NUMBER or are separately declared along with MAX_BIG_NUMBER.

• What is the motivation / use case for changing the behavior?
  To make it easy to align REopt.jl inputs and API v3.

• Please tell us about your environment:

  • REopt API Version: X.X.X
  • Operating System: [all | TypeScript X.X | ES6/7 | ES5 | Dart]
  • Python version: 3.x
  • Julia version: 1.x

• Other information (e.g. detailed explanation, stacktraces, related issues, suggestions how to fix, links for us to have context, eg. stackoverflow, gitter, etc)