On the SynologyWiki is an excellent article about installing Subversion on to your synology diskstation. Is is a step by step guide describing all the details for installing subversion on your diskstation.
Integrate Subversion and Visual Studio
You can also integrate SVN with your visual studio environment (almost like TFS). With the software from ankhSVN, for example, you can perfectly integrate SVN and Visual Studio (2008).
All other regular source control options, like banching and merging, labeling, shelving etcetera are all available.