hotfix: contrib/tnitter/net.xymus.tnitter.txt: terminate description

Signed-off-by: Jean Privat <jean@pryen.org>

Author: privat

contrib/tnitter/net.xymus.tnitter.txt

@@ -8,3 +8,4 @@ Summary:Minimal client for the Tnitter open source micro-blogging platform
 Description:
 Read the latest Tnits published on Tnitter and keep up to date with push notification support.
 This is a sample application to do asynchronous HTTP requests from portable Nit code.
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