Cosmetics - use of standard traits over specialized implementations

[Dirk007]

The changes in this PR are almost all cosmetics and for "rust"-ier feelings. Biggest change is the standard trait From implementation for the Seed which removes the formerly hard constraints on Seed-creation.

Type of change

• [X] Enhancement (a non-breaking change which adds functionality)

How the change has been tested

As almost everything is cosmetics, only a small test has been added to prove that the generated Seed via From is the same as the formerly used from_bytes().

Change checklist

Add an x to the boxes that are relevant to your changes, and delete any items that are not.

• [X] I have followed the contribution guidelines for this project
• [X] I have performed a self-review of my own code
• [X] I have commented my code, particularly in hard-to-understand areas
• [?] I have made corresponding changes to the documentation
• [X] I have added tests that prove my fix is effective or that my feature works
• [X] New and existing unit tests pass locally with my changes