themes: add keyword rounded_corners to our themes

Origin commit data
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Commit: 08cfcbc7f8
Author: vanhofen <vanhofen@gmx.de>
Date: 2019-02-11 (Mon, 11 Feb 2019)

Origin message was:
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- themes: add keyword rounded_corners to our themes

data/themes/AdulteratedOrange.theme

@@ -73,6 +73,7 @@ menu_Head_red=0
 menu_Hint_gradient=4
 menu_Hint_gradient_direction=1
 menu_Separator_gradient_enable=0
+rounded_corners=0
 progressbar_active_blue=0
 progressbar_active_green=70
 progressbar_active_red=95

data/themes/Material_Blue-Grey.theme

@@ -137,3 +137,5 @@ shadow_red=0
 shadow_green=0
 shadow_blue=0
 shadow_alpha=25
+
+rounded_corners=0

data/themes/Material_Grey_(Dark).theme

@@ -137,3 +137,5 @@ shadow_red=0
 shadow_green=0
 shadow_blue=0
 shadow_alpha=25
+
+rounded_corners=0

data/themes/Material_Grey_(Dark)_Orange.theme

@@ -119,3 +119,5 @@ shadow_red=0
 shadow_green=0
 shadow_blue=0
 shadow_alpha=25
+
+rounded_corners=0

data/themes/Material_Grey_(Light).theme

@@ -138,3 +138,5 @@ shadow_red=0
 shadow_green=0
 shadow_blue=0
 shadow_alpha=25
+
+rounded_corners=0

data/themes/Material_Grey_(Medium).theme

@@ -137,3 +137,5 @@ shadow_red=0
 shadow_green=0
 shadow_blue=0
 shadow_alpha=25
+
+rounded_corners=0