rust!: Update the minimal rustc version to 1.35.0

.gitlab-ci.yml

Cargo.lock

Cargo.toml

Makefile

README.md

src/binary/mod.rs

src/lib/builtins/calc.rs

src/lib/parser/lexers/arguments.rs

src/lib/shell/mod.rs

src/lib/shell/pipe_exec/fork.rs

src/lib/shell/pipe_exec/mod.rs

src/lib/shell/pipe_exec/streams.rs