Create CrySL rules for LTA

[kruegers]

CogniCrypt's code generator supports a solution for long time archiving (see #8). However, as of now, CogniCrypt_SAST does not, that is, it cannot check whether someone is using this solution correctly. To extend CogniCrypt_SAST's support, please develop CrySL rules for the involved LTA classes. Correspond with @mreif and @cwb38 in order to receive usage constraints.