Save multi reactions (pathway, single, edge cases) to RDF

[ivanmaslow]

As a User, I want to have the ability to save different reactions in RDF format, So that I can easily exchange data with other applications that use the same format.

Acceptance Criteria:

• User can save any kind of pathway or single reactions to RDF
• Save to RDF option will be available always.
• In cases, if there will be no reactions found - error should be displayed while saving to RDF.
• Static objects and reagents should be ignored.