plasmacli confirmsig query

[wesgraham]

Fixes #161
add support for plasmacli eth query sig <position>

[codecov-io]

Codecov Report

Merging #185 into develop will increase coverage by 0.27%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           develop     #185      +/-   ##
===========================================
+ Coverage    51.75%   52.02%   +0.27%     
===========================================
  Files           28       28              
  Lines         1314     1359      +45     
===========================================
+ Hits           680      707      +27     
- Misses         529      538       +9     
- Partials       105      114       +9

Impacted Files	Coverage Δ
cmd/plasmacli/store/keystore.go	40.5% <0%> (+5.66%)	⬆️

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[hamdiallam]

Nice work! Looks great.

Can you do a full test? (run a node, submit tx, another tx requiring the confrim signatures, the retrieve the confirm sig using this command; testing when no confirm signatures are present, etc).

[wesgraham]

Can you do a full test?

Tried depositing on the rootchain and running into a segfault