Add editor support for finding workflow elements

[glopesdev]

As workflows grow in size and complexity, it becomes more important to provide advanced editor search features. Specifically, we are aiming for the following find by features:

• name (or type name)
• property name
• property value
• element category

The scope of the find feature can be global or constrained to the selected workflow. The find results will be listed in a docked view expanding from the bottom of the editor, with each row displaying the specific find category (name, property, etc). Double-clicking on each find result will make the editor select the node (opening intermediate workflow editors if necessary).

[glopesdev]

An alternative approach to implementing find without requiring new UI elements is to follow the strategy of text editors and provide a command for finding the next or previous element from the current position of the cursor, and then moving the cursor to that position, e.g. with F3 or Shift+F3.

The search could also be triggered from the textbox with a new context menu that searches for workflow element name in the first instance.