(Nimbus-FML) Added first cut design of Intermediate Representation module

[jhugman]

Fixes SDK-399.

This PR introduces a module to represent a project or apps manifest of features.

Posted up early for feedback from @travis79.

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[codecov-commenter]

Codecov Report

Merging #4604 (f3b575d) into main (a5613c6) will increase coverage by 0.06%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #4604      +/-   ##
==========================================
+ Coverage   80.63%   80.69%   +0.06%     
==========================================
  Files          51       48       -3     
  Lines        5221     5217       -4     
==========================================
  Hits         4210     4210              
+ Misses       1011     1007       -4     

Impacted Files	Coverage Δ
components/support/nimbus-fml/src/lib.rs
components/support/nimbus-fml/src/main.rs
components/support/nimbus-fml/src/parser.rs

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[travis79]

The only concerns I have with this is naming it ir. While this is definitely an internal structure and we know what it represents, I lean towards naming this a little more descriptively intermediate_representation is wordy, but that might make where we use it more readable to an outside contributor, for instance. This is a strong opinion, weakly held, and I'm perfectly fine deferring to your preference on this

[travis79]

LGTM! Sorry for diverting on a naming bikeshed, but I think this is better self-documentation.