implemented static integer sets

..._primitives/src/main/rust_embedded/btypes/src/binteger.rs

btypes_primitives/src/main/rust_embedded/btypes/src/bset.rs

.../stups/codegenerator/generators/DeclarationGenerator.java

...u/stups/codegenerator/generators/ExpressionGenerator.java

.../de/hhu/stups/codegenerator/generators/TypeGenerator.java

...n/resources/de/hhu/stups/codegenerator/RustTemplate_e.stg

...va/de/hhu/stups/codegenerator/rust_embedded/TestSets.java