Update 3 NuGet dependencies (#5)

Bumps nanoFramework.CoreLibrary from 1.0.6-preview-001 to 1.0.6-preview-010.
Bumps nanoFramework.Runtime.Events from 1.0.2-preview-004 to 1.0.2-preview-017.
Bumps nanoFramework.System.Net from 1.0.2-preview-004 to 1.0.2-preview-013.

source/nanoFramework.System.Net.Http.nuspec

@@ -17,9 +17,9 @@
     <summary>nanoFramework.System.Net.Http assembly for nanoFramework C# projects</summary>
     <tags>nanoFramework C# csharp netmf netnf nanoFramework.System.Net.Http</tags>
     <dependencies>
-      <dependency id="nanoFramework.CoreLibrary" version="[1.0.6-preview-001]" />
-      <dependency id="nanoFramework.Runtime.Events" version="[1.0.2-preview-004]" />
-      <dependency id="nanoFramework.System.Net" version="[1.0.2-preview-004]" />
+      <dependency id="nanoFramework.CoreLibrary" version="[1.0.6-preview-010]" />
+      <dependency id="nanoFramework.Runtime.Events" version="[1.0.2-preview-017]" />
+      <dependency id="nanoFramework.System.Net" version="[1.0.2-preview-013]" />
     </dependencies>
   </metadata>
   <files>

source/nanoFramework.System.Net.Http/System.Net.Http.nfproj

@@ -62,24 +62,30 @@
     <None Include="packages.config" />
   </ItemGroup>
   <ItemGroup>
-    <Reference Include="mscorlib, Version=1.0.6.1, Culture=neutral, PublicKeyToken=c07d481e9758c731">
-      <HintPath>..\packages\nanoFramework.CoreLibrary.1.0.6-preview-001\lib\mscorlib.dll</HintPath>
+    <Reference Include="mscorlib, Version=1.0.6.10, Culture=neutral, PublicKeyToken=c07d481e9758c731">
+      <HintPath>..\packages\nanoFramework.CoreLibrary.1.0.6-preview-010\lib\mscorlib.dll</HintPath>
       <Private>True</Private>
     </Reference>
-    <Reference Include="nanoFramework.Runtime.Events, Version=1.0.2.4, Culture=neutral, PublicKeyToken=c07d481e9758c731">
-      <HintPath>..\packages\nanoFramework.Runtime.Events.1.0.2-preview-004\lib\nanoFramework.Runtime.Events.dll</HintPath>
+    <Reference Include="nanoFramework.Runtime.Events, Version=1.0.2.17, Culture=neutral, PublicKeyToken=c07d481e9758c731">
+      <HintPath>..\packages\nanoFramework.Runtime.Events.1.0.2-preview-017\lib\nanoFramework.Runtime.Events.dll</HintPath>
       <Private>True</Private>
     </Reference>
-    <Reference Include="System.Net, Version=1.0.2.4, Culture=neutral, PublicKeyToken=c07d481e9758c731">
-      <HintPath>..\packages\nanoFramework.System.Net.1.0.2-preview-004\lib\System.Net.dll</HintPath>
+    <Reference Include="System.Net, Version=1.0.2.13, Culture=neutral, PublicKeyToken=c07d481e9758c731">
+      <HintPath>..\packages\nanoFramework.System.Net.1.0.2-preview-013\lib\System.Net.dll</HintPath>
       <Private>True</Private>
     </Reference>
   </ItemGroup>
   <Import Project="$(NanoFrameworkProjectSystemPath)NFProjectSystem.CSharp.targets" Condition="Exists('$(NanoFrameworkProjectSystemPath)NFProjectSystem.CSharp.targets')" />
-  <Import Project="..\packages\Nerdbank.GitVersioning.2.2.13\build\Nerdbank.GitVersioning.targets" />
   <ProjectExtensions>
     <ProjectCapabilities>
       <ProjectConfigurationsDeclaredAsItems />
     </ProjectCapabilities>
   </ProjectExtensions>
+  <Import Project="..\packages\Nerdbank.GitVersioning.2.2.33\build\Nerdbank.GitVersioning.targets" Condition="Exists('..\packages\Nerdbank.GitVersioning.2.2.33\build\Nerdbank.GitVersioning.targets')" />
+  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
+    <PropertyGroup>
+      <ErrorText>This project references NuGet package(s) that are missing on this computer. Enable NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105.The missing file is {0}.</ErrorText>
+    </PropertyGroup>
+    <Error Condition="!Exists('..\packages\Nerdbank.GitVersioning.2.2.33\build\Nerdbank.GitVersioning.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\Nerdbank.GitVersioning.2.2.33\build\Nerdbank.GitVersioning.targets'))" />
+  </Target>
 </Project>

source/nanoFramework.System.Net.Http/packages.config

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="nanoFramework.CoreLibrary" version="1.0.6-preview-001" targetFramework="netnanoframework10" />
-  <package id="nanoFramework.Runtime.Events" version="1.0.2-preview-004" targetFramework="netnanoframework10" />
-  <package id="nanoFramework.System.Net" version="1.0.2-preview-004" targetFramework="netnanoframework10" />
-  <package id="Nerdbank.GitVersioning" version="2.2.13" developmentDependency="true" />
+  <package id="nanoFramework.CoreLibrary" version="1.0.6-preview-010" targetFramework="netnanoframework10" />
+  <package id="nanoFramework.Runtime.Events" version="1.0.2-preview-017" targetFramework="netnanoframework10" />
+  <package id="nanoFramework.System.Net" version="1.0.2-preview-013" targetFramework="netnanoframework10" />
+  <package id="Nerdbank.GitVersioning" version="2.2.33" developmentDependency="true" targetFramework="netnanoframework10" />
 </packages>