In kate-ctags, go to declaration if no definition found

For some languages, what would be commonly seen as the definition of a function does not get a ctags kind corresponding to a 'definition' type as listed in gotoDefinition(). For example, Python class member functions are of kind 'm', which kate-ctags identifies as a 'declaration' type in gotoDeclaration(). The result is that right now, using the 'Go to Definition' does not give any results while searching for a Python class member function. To overcome this while not jumping into the trouble of having a per-language type list, this is a proposal to simply try to find a 'declaration' if no 'definition' was found while looking for one.