separate line endings test data for dos and unix

Dependencies

• [2] 6HNRL5RT detect non-utf8 text files

Change contents

• replacement in libpijul/src/tests/data/1252.2 at line 0
  [2.4661]→[2.4662:4715](∅→∅)
  [2.4661]
• replacement in libpijul/src/tests/data/1252.1 at line 0
  [2.4725]→[2.4726:4779](∅→∅)
  [2.4725]
• file addition: 1252-dos.2 (-xw-x--x--)
  [2.4375]
• file addition: 1252-dos.1 (-xw-x--x--)
  [2.4375]