MN-631: validate version contract

[sansaian]

- What I did
validate contract version https://insolar.atlassian.net/wiki/spaces/DEV/pages/1508409428/heavy+node
- How I did it
add const with version
- How to verify it
run all test and starting mainnet and observer with auth service
- Description for the changelog

[codecov-commenter]

Codecov Report

Merging #50 into master will increase coverage by 0.59%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master      #50      +/-   ##
==========================================
+ Coverage   15.30%   15.90%   +0.59%     
==========================================
  Files           7        7              
  Lines        1006     1006              
==========================================
+ Hits          154      160       +6     
+ Misses        844      833      -11     
- Partials        8       13       +5     

Impacted Files	Coverage Δ
...solar/mainnet/application/appfoundation/helpers.go	10.52% <0.00%> (ø)
...et/application/builtin/contract/deposit/deposit.go	2.64% <0.00%> (+2.64%)	⬆️

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