Add placeholder for calling manager theme (small fix)

https://github.com/dmi3yy/evolution/commit/1785f2d551abbec805817819354f592dfce80873

http://forums.modx.com/thread/83707/change-manager-theme-with-login-screen#dis-post-462019
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Add placeholder for calling manager theme (small fix)
Merge pull request #41 from yama/1.0.10

Add placeholder for calling manager theme (small fix)