DebugSymbols is ignored if DebugType is set.

The Fody project recently had an issue where debug symbols were not being processed properly in release mode.

https://github.com/Fody/Fody/issues/360

It turns out that the value of `DebugSymbols` is completely ignored if `DebugType` is set.

https://github.com/Microsoft/msbuild/blob/master/src/Tasks/Microsoft.Common.CurrentVersion.targets#L145-L151

<_DebugSymbolsProduced>false
<_DebugSymbolsProduced Condition="'$(DebugSymbols)'=='true'">true
<_DebugSymbolsProduced Condition="'$(DebugType)'=='none'">false
<_DebugSymbolsProduced Condition="'$(DebugType)'=='pdbonly'">true
<_DebugSymbolsProduced Condition="'$(DebugType)'=='full'">true
<_DebugSymbolsProduced Condition="'$(DebugType)'=='portable'">true
<_DebugSymbolsProduced Condition="'$(DebugType)'=='embedded'">false

But according to the documentation DebugSymbol should control the output of the symbol file.

https://msdn.microsoft.com/en-us/library/bb629394.aspx

> **DebugSymbols** A boolean value that indicates whether symbols are generated by the build. Setting /p:DebugSymbols=false on the command line disables generation of program database (.pdb) symbol files.

> **DebugType** Defines the level of debug information that you want generated. Valid values are "full," "pdbonly," and "none."

Is this a bug?