Normalize the final new line

Fixes #310
Some files had no newlines, some had 1 newline and some more than 1 newline.
Normalize them all to have only 1 newline at the end of all files.

pages/common/sed.md

@@ -18,5 +18,3 @@
 - replace all occurrences of multiple strings in a file
 
 `sed -e 's/{{find}}/{{replace}}/g' -e 's/{{find}}/{{replace}}/g' {{filename}}`
-
-