Fix nuspec for WebServer.FileSystem nuget (#228)

Author: Ellerbach

nanoFramework.WebServer.FileSystem.nuspec

@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <package xmlns="http://schemas.microsoft.com/packaging/2012/06/nuspec.xsd">
   <metadata>
-    <id>nanoFramework.WebServer.FileServer</id>
-    <title>nanoFramework.WebServer.FileServer</title>
+    <id>nanoFramework.WebServer.FileSystem</id>
+    <title>nanoFramework.WebServer.FileSystem</title>
     <version>$version$</version>
     <authors>Laurent Ellerbach,nanoframework</authors>
     <requireLicenseAcceptance>false</requireLicenseAcceptance>
@@ -29,7 +29,7 @@ Otherwise use 'nanoFramework.WebServer' nuget.</description>
     </dependencies>
   </metadata>
   <files>
-    <file src="nanoFramework.WebServer\bin\Release\nanoFramework.WebServer.*" target="lib" />
+    <file src="nanoFramework.WebServer.FileSystem\bin\Release\nanoFramework.WebServer.*" target="lib" />
     <file src="assets\readme.txt" target="" />
     <file src="README.md" target="docs\" />
     <file src="assets\nf-logo.png" target="images" />