Protecting the architecture "contains" test against null pointer exceptions
Started a new workflow element to iterate a single rate IBSDF graph (duplicate the graph).

Signed-off-by: mpelcat <mpelcat@insa-rennes.fr>
Duplicating IBSDF in IterateAlgorithm workflow element
Created a org.ietr.preesm.utils plug-in.
org.ietr.preesm.utils.files contains FilesManager.xtend and Result.java, utils to:
-compare contents of files
-read and write files
-extract files from JARs
Added a ContainersManager.java class to org.ietr.preesm.utils.files
This class is a util to create and delete IProject and IFolder inside a workspace
Added a bundleFilter parameter to the getUrl method, to be able to filter bundles in which to look for a File
Format
Added a getFile method to FilesManager.xtend to return a file using its path and a bundle filter
Modified the findScripts to use FilesManager and ContainersManager and to cache already found script files.
Embedded scripts for special vertices (fork, join, broadcast and roundbuffers) are now found even in release version.
Moved createMissingFolders method from org.ietr.dftools.ui.util.FileUtils to org.ietr.preesm.utils.files.ContainersManager
Merge branch 'preesm-utils' into develop
PREESM Release 2.1.2