Improve LR and SSA (add them to metamodel and make relations bidirectionals)

[jecisc]

This PR metadescribe entities related to LR and SSA and their properties to that those can be queriable and gets exported if we export the model.

I also made relations bidirectionals:

• #localDeclaration/#localUses are now opposites so that we do not need to duplicate those relations
• #choices (on Phi versions) now has an opposite #phiVersionContainers so that a SSAVersion knows which phi versions contains them
• #ssaVersion now has an opposite #nodes so that a SSAVersion knows all nodes it concerns

[jecisc]

Oh this also adds comments to SSA classes

[coveralls]

Coverage Report for CI Build 36581979697

Coverage decreased (-0.7%) to 24.049%

Details

• Coverage decreased (-0.7%) from the base build.
• Patch coverage: 57 uncovered changes across 4 files (6 of 63 lines covered, 9.52%).
• 2 coverage regressions across 2 files.

Uncovered Changes

File	Changed	Covered	%
src/FAST-Core-Tools/FASTAbstractVariableVersionSSA.class.st	22	0	0.0%
src/FAST-Core-Tools/FASTVariableVersionSSA.class.st	17	0	0.0%
src/FAST-Core-Tools/FASTVariablePhiVersionSSA.class.st	12	0	0.0%
src/FAST-Core-Tools/FASTNonLocalDeclaration.class.st	6	0	0.0%
Total (6 files)	63	6	9.52%

Coverage Regressions

2 previously-covered lines in 2 files lost coverage.

File	Lines Losing Coverage	Coverage
src/FAST-Core-Tools/FASTAbstractVariableVersionSSA.class.st	1	0.0%
src/FAST-Core-Tools/FASTVariablePhiVersionSSA.class.st	1	0.0%

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Coverage Stats

Relevant Lines:	1813
Covered Lines:	436
Line Coverage:	24.05%
Coverage Strength:	0.48 hits per line

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💛 - Coveralls

[jecisc]

Also note that if you want your versions to be exported, you need to add their instances to the moose model