Export graphs with PE folder name included in the name of the exported file

Version: 2018b

Type: Features

Category: Graphing

Subcategory: Publishing

Jira: ORG-17252

We introduce a new keyword like <PE parent1> which refers to the immediate parent folder name.
We can for now support up to 3 levels, so we will support <PE parent2>&<PE parent3>, but show only <PE parent1>-<long name> on GUI for now.