Special transaction gas limit update

Proposal is to increase special_gas_limit from 35'000'000 to 70'000'000 in Config Parameter 20.

Old configuration:

(config_mc_gas_prices
  (gas_flat_pfx flat_gas_limit:100 flat_gas_price:1000000
    other:(gas_prices_ext gas_price:655360000 gas_limit:1000000 special_gas_limit:35000000 gas_credit:10000 block_gas_limit:2500000 freeze_due_limit:100000000 delete_due_limit:1000000000)))

Proposed configuration:

(config_mc_gas_prices
  (gas_flat_pfx flat_gas_limit:100 flat_gas_price:1000000
    other:(gas_prices_ext gas_price:655360000 gas_limit:1000000 special_gas_limit:70000000 gas_credit:10000 block_gas_limit:2500000 freeze_due_limit:100000000 delete_due_limit:1000000000)))

Currently elections consume about 32'000'000 units of gas that is dangerously close to current limit of 35'000'000. Acceptance of the proposal will ensure smooth conduct of the elections.

To participate in voting, validators that use MyTONCtrl will need to execute one command in MyTONCtrl console, while validators that do not use MyTONCtrl will need create vote-message with validator-engine-console and then send it (via lite-client or tonapi/toncenter) each round until proposal is accepted, documentation can be found here. Exact instructions for both cases will be available on July 2.