* if we got no data from the server in the haltestelle.processabfahrten() method, we call haltestelle.getHaltestellen() method
* when we got data from the server in the haltestelle.getHaltestellen() method, we call the haltestelle.processHaltestellen() method
* in the haltestelle.processHaltestellen() method we process the gotten data and print it into the output area of the html file

* new method haltestelle.getHaltestellen() to get the station names from the server
* new method haltestelle.processHaltestellen() to process the received station names
* event handler registration for haltestelle.getHaltestellen() method

* combined various variable defintions
* moved the invocation into the parens that contain the function
* some minor things

* dependent on the window.location.protocol result, we construct the serverUrl
* for strato ssl-proxy, we hve to insert the 1st part of the window.location.path result

* rename 'haltestelle.getInfo()' method to 'haltestelle.getAbfahrten()'
* move the ajax response processing from the anonymous callback function in the'haltestelle.getAbfahrten()' method into own 'haltestelle.processAbfahrten()' method
* adapt the eventListener to the renaming into the 'haltestelle.getAbfahrten()' method

* if it's empty don't process it and print a message into html
* if there is useful data, process is and print the data as table into html

* check for the origin of the url (with or without www) to select the suitable ajax url to fullfill the same origin policy

* we get our data now from a python script on same server as the webpage
* url was changed to our own server
* we must delete one char more at begin and end of the response string

* ajaxCall() function now with parameter for type of response value, available values: "text", "xml" & "json"

some more comments for documentation