Don't bother looking in that file, it will only tell you the same thing - that the package failed to load.
You have installed a Visual Studio extension package (it may have been installed by another piece of software), and these are not compatible with SSMS, and yes I would say it is a bug, but it as been present since SQL 2008 and is still there in 2014, so not much chance of a fix.
The only way to stop the error you are seeing (short of a hack) is to remove the extension from SSMS.
Extension packages can be stored pretty much anywhere on the client, but the usual places are in your user profile (%LOCALAPPDATA%)
e.g. C:\Users\mister.magoo\AppData\Local\Microsoft\SQL Server Management Studio\12.0\Extensions
or under the SSMS installation folders
e.g. C:\Program Files (x86)\Microsoft SQL Server\120\Tools\Binn\ManagementStudio\Extensions
The actual extension folder will be named something absurd like z05we0ea.mff, and you can remove it by simply deleting the folder when SSMS is not running.
**WARNING** Make sure you get the correct folder!!! And back it up first!!! **
MM
select geometry::STGeomFromWKB(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