Add a public Eval() function for indexer

[tolikzinovyev]

Summary

Add a public Eval() function in ledger that Indexer can use. The function accepts a custom protocol config so that Indexer can override it to always get asset close amounts, as opposed to only when the protocol supports it.

Closes https://github.com/algorand/go-algorand-internal/issues/1211.

Test Plan

What kind of test can I write?

[codecov-commenter]

Codecov Report

Merging #2662 (7795c82) into master (911bb55) will decrease coverage by 0.00%.
The diff coverage is 33.33%.

@@            Coverage Diff             @@
##           master    #2662      +/-   ##
==========================================
- Coverage   47.02%   47.02%   -0.01%     
==========================================
  Files         349      349              
  Lines       55814    55833      +19     
==========================================
+ Hits        26247    26254       +7     
- Misses      26617    26627      +10     
- Partials     2950     2952       +2     

Impacted Files	Coverage Δ
ledger/eval.go	75.00% <33.33%> (-1.69%)	⬇️
catchup/service.go	68.57% <0.00%> (-0.78%)	⬇️
ledger/acctupdates.go	61.80% <0.00%> (-0.51%)	⬇️
data/transactions/verify/txn.go	48.45% <0.00%> (ø)
network/requestTracker.go	71.12% <0.00%> (+0.86%)	⬆️
network/wsPeer.go	75.20% <0.00%> (+3.06%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 911bb55...7795c82. Read the comment docs.

[tsachiherman]

looks good to me.