[WIP] Argument caching

[kmike]

This PR should allow to save network traffic by caching large argument values on server.

See also: #283.

[codecov-io]

Current coverage is 85.85%

Merging #442 into master will increase coverage by +0.14% as of 709ca8a

@@            master    #442   diff @@
======================================
  Files           39      40     +1
  Stmts         4628    4729   +101
  Branches       633     652    +19
  Methods          0       0       
======================================
+ Hit           3967    4060    +93
- Partial        156     159     +3
- Missed         505     510     +5

Review entire Coverage Diff as of 709ca8a

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