MODE-1937 Corrected the Java sequencer's generated method nodes

Nodes representing methods were named with the method name and parameter names, but this was changed to be closer to the standard Java signature of method name and parameter types. This makes it possible to properly support overloaded methods and constructors.

Several of the existing tests were modified to use overloaded constructors and methods, and all pass with these changes. Note that no changes in the node types were required, though the sequencer's generated content is now slightly different (only in terms of the method and constructor node names).