add missing properties to translations

[SepidehAlassi]

For the next import, in translated letters add following properties: For example in L002-T

• link to original letter as below: `

  </beol:letterHasOriginal>`

• translation of reply to: `

  </beol:letterIsReplyTo>`

check the GUI representation of these properties

[SepidehAlassi]

add properties to translated letters