Revert "Fix GetTrust throwing an exception if no such trust exists:"

This reverts commit f08067fc86a37ccf031618436587ee794ea17b55.

- Since addTrustFields() is used in code which also uses addScoreFields() to add stuff to the same SFS, the names would collide.
Therefore, I will have to revert the whole of the commits which merged addTrustFields() with handleGetTrust().
Revert "JavaDoc:"

This reverts commit cf845cc777557185eb300806daffa4e677f96408.

- Since addTrustFields() is used in code which also uses addScoreFields() to add stuff to the same SFS, the names would collide.
Therefore, I will have to revert the whole of the commits which merged addTrustFields() with handleGetTrust().
Revert "Remove code duplication:"

This reverts commit 5422cd93e2f9c7bf85e01e7d34bb3493faed3807.

- Since addTrustFields() is used in code which also uses addScoreFields() to add stuff to the same SFS, the names would collide.
Therefore, I will have to revert the whole of the commits which merged addTrustFields() with handleGetTrust().