Remove DebuggerBrowsable from excluded classes (#78)

Author: josesimoes

source/nanoFramework.CoreLibrary/CoreLibrary.nfproj

@@ -226,12 +226,6 @@
     <NFMDP_PE_ExcludeClassByName Include="System.Diagnostics.DebuggableAttribute">
       <InProject>false</InProject>
     </NFMDP_PE_ExcludeClassByName>
-    <NFMDP_PE_ExcludeClassByName Include="System.Diagnostics.DebuggerBrowsableAttribute">
-      <InProject>false</InProject>
-    </NFMDP_PE_ExcludeClassByName>
-    <NFMDP_PE_ExcludeClassByName Include="System.Diagnostics.DebuggerBrowsableState">
-      <InProject>false</InProject>
-    </NFMDP_PE_ExcludeClassByName>
     <NFMDP_PE_ExcludeClassByName Include="System.Diagnostics.DebuggerDisplayAttribute">
       <InProject>false</InProject>
     </NFMDP_PE_ExcludeClassByName>