+ libsodium.lib for Windows, iguana needed BLAKE2b-256 calc for preimage

before build iguana under Windows you should download and compile
libsodium.lib & libsodium.dll by using iguana_build_depends.cmd .
in marketmaker this accomplished by using cmake, but iguana didn't use
cmake build.

iguana.vcxproj

@@ -120,7 +120,7 @@
       <SubSystem>Console</SubSystem>
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <AdditionalLibraryDirectories>.\OSlibs\win\x64;%(AdditionalLibraryDirectories)</AdditionalLibraryDirectories>
-      <AdditionalDependencies>pthread_lib.lib;Ws2_32.lib;nanomsg.lib;libcurl.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <AdditionalDependencies>pthread_lib.lib;Ws2_32.lib;nanomsg.lib;libcurl.lib;libsodium.lib;%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
@@ -160,7 +160,7 @@
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
       <GenerateDebugInformation>true</GenerateDebugInformation>
-      <AdditionalDependencies>Ws2_32.lib;Advapi32.lib;$(SolutionDir)OSlibs\win\x64\pthread_lib.lib;libcurl.lib;nanomsg.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <AdditionalDependencies>Ws2_32.lib;Advapi32.lib;$(SolutionDir)OSlibs\win\x64\pthread_lib.lib;libcurl.lib;nanomsg.lib;libsodium.lib;%(AdditionalDependencies)</AdditionalDependencies>
       <AdditionalLibraryDirectories>.\OSlibs\win\x64\release;%(AdditionalLibraryDirectories)</AdditionalLibraryDirectories>
     </Link>
   </ItemDefinitionGroup>

iguana_build_depends.cmd

@@ -0,0 +1,71 @@
+@echo off
+rem [ Decker] Automatically download and build depends script for marketmaker.
+rem
+rem 1. Requires installed CMake for Windows (!)
+rem 2. Currently build only 64-bit release versions of .lib and .dll
+rem 3. Libraries available: pthreads, nanomsg, curl
+
+@REM Check for Visual Studio
+call set "VSPATH="
+if defined VS140COMNTOOLS ( if not defined VSPATH (
+ call set "VSPATH=%%VS140COMNTOOLS%%"
+) )
+
+@REM check if we already have the tools in the environment
+if exist "%VCINSTALLDIR%" (
+ goto compile
+)
+
+if not defined VSPATH (
+ echo You need Microsoft Visual Studio 15 installed
+ pause
+ exit
+)
+
+@REM set up the environment
+if exist "%VSPATH%..\..\vc\vcvarsall.bat" (
+ call "%%VSPATH%%..\..\vc\vcvarsall.bat" amd64
+ goto compile
+)
+
+echo Unable to set up the environment
+pause
+exit
+
+:compile
+rem MSBuild /help
+echo.
+echo Decker will automatically download and build all needed *.dll and *.lib for you ;)
+
+mkdir iguana_depends
+mkdir x64\Release
+
+rem --- libsodium ---
+rem https://libsodium.gitbook.io/doc/installation
+
+:compile_libsodium
+
+if not exist iguana_depends\libsodium\bin\x64\Release\v140\dynamic\libsodium.lib (
+cd iguana_depends
+git clone https://github.com/jedisct1/libsodium
+cd libsodium
+cd "builds\msvc\vs2015" 
+MSBuild libsodium.sln /t:Rebuild /p:Configuration=DynRelease /p:Platform=x64
+MSBuild libsodium.sln /t:Rebuild /p:Configuration=DynDebug /p:Platform=x64
+cd ../../..
+cd ..
+)
+
+copy iguana_depends\libsodium\bin\x64\Release\v140\dynamic\libsodium.lib OSlibs\win\x64\release\libsodium.lib
+copy iguana_depends\libsodium\bin\x64\Release\v140\dynamic\libsodium.exp OSlibs\win\x64\release\libsodium.exp
+copy iguana_depends\libsodium\bin\x64\Release\v140\dynamic\libsodium.dll x64\Release\libsodium.dll
+
+rem mkdir OSlibs\win\x64\debug
+rem libs for configuration: Debug stored in OSlibs\win\x64 (check .sln)
+copy iguana_depends\libsodium\bin\x64\Debug\v140\dynamic\libsodium.lib OSlibs\win\x64\libsodium.lib
+copy iguana_depends\libsodium\bin\x64\Debug\v140\dynamic\libsodium.exp OSlibs\win\x64\libsodium.exp
+copy iguana_depends\libsodium\bin\x64\Debug\v140\dynamic\libsodium.dll x64\Debug\libsodium.dll
+
+mkdir includes\sodium
+xcopy /E /Y iguana_depends\libsodium\src\libsodium\include\sodium includes\sodium
+copy iguana_depends\libsodium\src\libsodium\include\sodium.h includes\