Eliminate dependence on most uniswap functions

lib_sol8/v3-periphery/contracts/interfaces/IPeripheryImmutableState.sol

@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+pragma solidity >=0.5.0;
+
+/// @title Immutable state
+/// @notice Functions that return immutable state of the router
+interface IPeripheryImmutableState {
+    /// @return Returns the address of the Uniswap V3 factory
+    function factory() external view returns (address);
+
+    /// @return Returns the address of WETH9
+    function WETH9() external view returns (address);
+}