inspector: Correct a tooltip
inspector: Improve search in the resource tree

Make search in the resource tree work the same way as the new
search in the object tree.
inspector: Shorten some labels
inspector: Move the record button up

Give all the page space to the content.
inspector: Improve search on the statistics page

Use a search bar here as well, instead of the builtin treeview popup.
extract-strings: Handle property binding attributes

These attributes are now used in at least one place in the
GtkInspector ui files.
inspector: Reserve space for buttons

Make the button area in the top left a stack that is parallel
to the main page stack. This avoids size changes as we switch
between pages.