LOG4NET-540 add empty dependency groups for all supported target frameworks
diff --git a/log4net.nuspec b/log4net.nuspec
index 3a0b42a..27fac16 100644
--- a/log4net.nuspec
+++ b/log4net.nuspec
@@ -39,6 +39,12 @@
<requireLicenseAcceptance>false</requireLicenseAcceptance>
<tags>logging log tracing logfiles</tags>
<dependencies>
+ <group targetFramework="net20-full" />
+ <group targetFramework="net35-full" />
+ <group targetFramework="net40-full" />
+ <group targetFramework="net45-full" />
+ <group targetFramework="net35-client" />
+ <group targetFramework="net40-client" />
<group targetFramework=".NETStandard1.3">
<dependency id="System.AppContext" version="[4.1.0, )" />
<dependency id="System.Collections.NonGeneric" version="[4.0.1, )" />