Implemented brainflakes

src/combinators/combinators.rs

src/examples/brainflakes/brainflakes_1.bf

src/examples/brainflakes/brainflakes_parser.rs

src/examples/brainflakes/brainflakes_parser_components.rs

src/examples/brainflakes/hello_world.bf

src/examples/brainflakes/mod.rs

src/examples/brainfuck/mod.rs

src/examples/example_programs/arithmetic/expression.rs

src/examples/mod.rs

src/main.rs

src/parser/mod.rs

src/parser/parser.rs

src/parser_impls/chars.rs

src/parser_impls/ints.rs

src/parser_impls/whitespace.rs

src/tests/example_parser_tests.rs

src/tests/tests.rs