2011-01-25 : path produced w/o '/' or weird characters

2011-01-25 : cannot set global attribute if it is an attribute that can be set via cmor_dataset
2011-01-25 : cannot set var attribute after var has been created into nc file
2011-01-25 : cannot set var attribute if it is settable via cmor_variable
2011-01-25 : can handle "character type" singleton dimensions
2011-01-25 : does not stores units on character typevariables
2011-01-24 : cmor_axes, interval check cleanup errormessage, now specifies which units the diff calaculated is in.
2011-01-24 : updated cmor_set_variable_attrubtes to go thru an 'internal' one