[gtk] Rename the project's DOAP file

[Emmanuele Bassi <ebassi src gnome org>]

commit ff41829b3f75d5b3b112cba280cbf8f0e982dfd4
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Thu Feb 8 14:11:12 2018 +0000

    Rename the project's DOAP file
    
    We need its name to match the repository's name.

 gtk+.doap => gtk.doap | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
---
diff --git a/gtk+.doap b/gtk.doap
similarity index 100%
rename from gtk+.doap
rename to gtk.doap