add interfaces to implement observer-subject-pattern #70
initial commit
delete obsolete Observer and SubjectInterface #69
update sql_schema #69
User: add functions to create, delete, get and update an user #70
ModelController: add logic to use the right parameters for the right modelfunction #70
RequestHandler: update handleRequest() to get params from rewritten url #70
RequestHandler: update handleRequest() to check if GET_Request is find or findAll #70
User: add findAll-function
ModelController: call findAll-function #70
 update .htaccess #72 fixed
add to_array function and ArraySerializer #69
User: add return statements #69
ModelController: add return statements #69
RequestHandler: add basic response functionality
delete ResponseFactory #73
RequestHandler: delete obsolete require-statement #69
update CredentialsReader and implement it in ModelController  #75 fixed
refactor Tickets and User, delete implemented SubjectInterface #69
fix issue annotated by Panther #69
implement CredentialsReader #75 fixed
implement basic exceptionhandling. i commit this because i wanna work on the task tomorrow on a different laptop. so pls don't consider#69