Update assembly info file for v1.0.0-preview008

[version update]

Author: nfbot

source/nanoFramework.System.Net.Http/Properties/AssemblyInfo.cs

@@ -25,7 +25,7 @@
 //
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
-// [assembly: AssemblyVersion("1.0.*")]
+// [assembly: AssemblyVersion("1.0.0.0")]
 [assembly: AssemblyVersion("1.0.0.0")]
 [assembly: AssemblyFileVersion("1.0.0.0")]
-[assembly: AssemblyInformationalVersion("1.0.0-rc001")]
+[assembly: AssemblyInformationalVersion("1.0.0-preview008")]