Add support for ignoring single method calls in the trace

[alpaca-tc]

Extended ignored_method_ids.

Previously, all call stacks after the specified method was ignored.
After this PR changes, you can choose to exclude only the call stack of that method from tracing instead of full call stack.

The way options are specified has changed.

# before
ignored_method_ids: ['A.class_call']

# after
ignored_method_ids: {
  'A.class_call' => :full, # same original behavior
  'A.bar' => :single # new behavior
}