Split DB.cs into its proper files

Having a nearly 1500 line file isn't real cool.

Author: golf1052

Signal-Windows.Lib/IncomingMessages.cs

@@ -1,4 +1,9 @@
-using libsignal.messages.multidevice;
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Threading;
+using System.Threading.Tasks;
+using libsignal.messages.multidevice;
 using libsignalservice;
 using libsignalservice.crypto;
 using libsignalservice.messages;
@@ -8,15 +13,6 @@
 using Microsoft.Extensions.Logging;
 using Signal_Windows.Models;
 using Signal_Windows.Storage;
-using System;
-using System.Collections.Generic;
-using System.Diagnostics;
-using System.IO;
-using System.Linq;
-using System.Text;
-using System.Threading;
-using System.Threading.Tasks;
-using Windows.Storage;
 using static libsignalservice.SignalServiceMessagePipe;
 
 namespace Signal_Windows.Lib

Signal-Windows.Lib/Signal-Windows.Lib.csproj

@@ -119,6 +119,8 @@
     <Compile Include="Settings\LocalConfigurationSource.cs" />
     <Compile Include="Settings\SignalSettings.cs" />
     <Compile Include="SignalWebSocket.cs" />
+    <Compile Include="Storage\LibsignalDBContext.cs" />
+    <Compile Include="Storage\SignalDBContext.cs" />
     <Compile Include="Util\LibUtils.cs" />
     <Compile Include="Migrations\LibsignalDB\20170806145530_ls1.cs" />
     <Compile Include="Migrations\LibsignalDB\20170806145530_ls1.Designer.cs">
@@ -164,7 +166,6 @@
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="SignalLibHandle.cs" />
     <Compile Include="SignalLogging.cs" />
-    <Compile Include="Storage\DB.cs" />
     <Compile Include="Storage\Store.cs" />
     <Compile Include="Util\NotificationsUtils.cs" />
     <EmbeddedResource Include="Properties\Signal_Windows.Lib.rd.xml" />