add scripting course and file manipulation

README.md

docs/pages/bash/bash-1-introduction.md

docs/pages/bash/bash-2-the-basics.md

docs/pages/bash/bash-7-commands.md

docs/pages/bash/bash-8-loops.md

docs/pages/bash/bash-9-scripting.md

docs/pages/bash_file/bash-extracting_from_files.md

docs/pages/bash_script/bash_script-1-intro.md

docs/pages/bash_script/bash_script-2-data_structure.md

docs/pages/bash_script/bash_script-3-conditional.md

docs/pages/bash_script/bash_script-4-loop.md

docs/pages/bash_script/bash_script-5-argument.md

docs/pages/bash_script/bash_script-6-function.md

docs/pages/bash_script/bash_script-7-interface.md

mkdocs.yml