We are working with a PHP application which has no concept of switch-able themes; the situation is that we are modifying the application to add our own features, and CSS/Smarty templates for our own look and feel.
We have 2 projects base on this application, each with a different layout/presentation. Hence I need to have the repository to store both css/templates, but somehow am able to 'merge' in the right one for the respective project. How can this be done?
Either you create two repositories and use the external link functionality to "include" the other repository or you simply create folders at the base leveln of the repository and put the projects there.
RepoBase/Project1/trunk/
RepoBase/Project1/tags/
RepoBase/Project1/branches/
RepoBase/Project2/trunk/
RepoBase/Project2/tags/
RepoBase/Project2/branches/
If both projects are depending a lot on each other, you might even choose this layout:
RepoBase/trunk/project1
RepoBase/trunk/project2
RepoBase/tags/project1
RepoBase/tags/project2
RepoBase/branches/project1
RepoBase/branches/project2
Here is how you include external references in a repo:
http://svnbook.red-bean.com/en/1.4/svn-book.html#svn.advanced.externals
Short version: there is no such thing as nested repository. Google for svn externals.