No Side_both available in privateService.proto + default value is Side_buy not "Side_both"

[direktoren]

Bug Description Documentation https://lykkecity.github.io/Trading-API/#mass-cancel-orders say query parameter for Mass cancel orders when you select a side to cancel:

side | string | query | null | (Optional) Order side Buy or Sell (both sides by default).

But the privateService.proto definition say

message CancelOrdersRequest {
    string assetPairId = 1;
    Side side = 2;
}

where Side is

enum Side {
    buy = 0;
    sell = 1;
}

Issue number #1

• Default becomes "buy" not "both" since 0 is same as no value for some languages

Issue number #2

• There is no "both" option for Side.

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Last upstream Slate commit (run git log --author="Robert Lord" | head -n 1): Latest