The tracepoints are getting a better visual representation on the
timelinewidget so this is no longer necessary.

Move the tracepoints from TimeAxisHeaderView to TimeLineWidget so that
we can use the header for cpu usage.
This also improves usability since the tracepoints are no longer bundles
in one line. They now each have their own line.

Enum automatically counts up so there is no need to manually set these
values.

this allows the user to group important timelines together so that he
can compare them better

The favourites and tracepoint patches include some rows in the model
that may be empty. To keep the code simple an readable all rows will be
shown. Then a proxy model is put ontop to remove empty rows.

This way we can more easily find them and changing the sort order
doesn't move them to the bottom.

Showing only one cost is fine if we only show a hardware event, but
since we now support tracepoints and some come in an enter/exit pair it
requires us to rework the timeline delegate.
This patch makes the event source combobox multi select and allows to
select multiple event sources.

This patch allows hotspot to correctly parse most format string from the
tracepoint definition. If that fails every entry in the tracepoint will
be printed unformatted. In this case it is possible to add a custom
formatter.