added tank node and tank link
files dont get overritten now.
changed a few missleading varibales names
added combobox where the user can select the city
changed output file names
changed way of reading input:
line numer 2 doesnt gets skipped anymore because the format of the input file changed
added new combobox
annualrain differs according to selection in combobox
outputfile doesnt gets overritten anymore
tanknode is added
generated files (.msf .mcf .bat) are ending on TP now