l10n: Updated Sinhala (si) translation to 10%

New status: 8 messages complete with 0 fuzzies and 67 untranslated.

Transmitted-via: Transifex (translations.xfce.org).

po/si.po

@@ -107,11 +107,11 @@ msgstr ""
 #. Save option radio button
 #: ../lib/screenshooter-dialogs.c:936
 msgid "Save"
-msgstr ""
+msgstr "සුරකින්න"
 
 #: ../lib/screenshooter-dialogs.c:941
 msgid "Save the screenshot to a PNG file"
-msgstr ""
+msgstr "තිරපිටපත PNG ගොනුවකට සුරකින්න"
 
 #: ../lib/screenshooter-dialogs.c:950
 msgid "Copy to the clipboard"