feat(core-snapshots): add support for transaction nonces

[vasild]

A summary of what changes this PR introduces and why they were made.

What kind of change does this PR introduce?

• Bugfix
• Feature
• Refactor
• Performance
• Tests
• Build
• Documentation
• Code style update
• Continuous Integration
• Other, please describe:

Does this PR introduce a breaking change?

• Yes
• No

Does this PR release a new version?

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

The PR fulfills these requirements:

• It's submitted to the develop branch, not the master branch
• All tests are passing
• New/updated tests are included

If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature (to avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it)

[spkjp]

I get the following error when I restore a fresh dump made on this branch:

[2019-09-13 23:58:15.022] DEBUG: Connected to database.
[2019-09-13 23:58:15.159] WARN : No block found in database
[2019-09-13 23:58:15.209] INFO : Starting to import table blocks from /home/supaiku/.local/share/ark-core/testnet/snapshots/1-1905287/blocks, skipCompression: false
100% | ETA: 0s | 1905287/1905287 | Duration: 185s
[2019-09-14 00:01:19.960] INFO : Starting to import table transactions from /home/supaiku/.local/share/ark-core/testnet/snapshots/1-1905287/transactions, skipCompression: false
100% | ETA: 0s | 463301/463301 | Duration: 74serror: invalid input syntax for integer: "{"s":1,"e":3,"c":[2158],"_isBigNumber":true}"
    at Connection.parseE (~/git/ark-core/node_modules/pg/lib/connection.js:602:11)
    at Connection.parseMessage (~/git/ark-core/node_modules/pg/lib/connection.js:399:19)
    at Socket.<anonymous> (~/git/ark-core/node_modules/pg/lib/connection.js:121:22)
[2019-09-14 00:02:34.541] INFO : Core is trying to gracefully shut down to avoid data corruption

[spkjp]

broken

[codecov-io]

Codecov Report

Merging #2925 into develop will decrease coverage by <.01%.
The diff coverage is 75%.

@@             Coverage Diff             @@
##           develop    #2925      +/-   ##
===========================================
- Coverage    65.83%   65.82%   -0.01%     
===========================================
  Files          424      424              
  Lines        10167    10169       +2     
  Branches       538      540       +2     
===========================================
+ Hits          6693     6694       +1     
- Misses        3428     3429       +1     
  Partials        46       46

Impacted Files	Coverage Δ
packages/core-snapshots/src/transport/codec.ts	85.45% <75%> (-1.34%)	⬇️

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[vasild]

Steps to reproduce would be useful, thanks!