Edit farsi translation and add 'words'

I suggest more comfortable translation for 'prev_page' and 'next_page'.
Also, I added farsi translation for missing 'words'.

i18n/fa.yaml

@@ -1,19 +1,24 @@
 - id: prev_page
-  translation: "صفحه قبلی"
+  translation: "صفحه قبل"
 
 - id: next_page
-  translation: "صفحه بعدی"
+  translation: "صفحه بعد"
 
 - id: read_time
   translation:
-    one: "۱ دقیقه"
+    one : "1 دقیقه"
     other: "{{ .Count }} دقیقه"
 
+- id: words
+  translation:
+    one : "کلمه"
+    other: "{{ .Count }} کلمه"
+
 - id: toc
   translation: "فهرست مطالب"
 
 - id: translations
-  translation: "ترجمه ها"
+  translation: "ترجمه‌ها"
 
 - id: home
   translation: "خانه"
@@ -25,4 +30,4 @@
   translation: "کپی"
 
 - id: code_copied
-  translation: "کپی شد!"
+  translation: "کپی شد!"