Varst

Feat

- Add save function to save documnet object as rst file
- Add replace_substitution function
- Add substitution_text function to find substitution text
- Add substitution_def_node function to find substitution_def node
- Create rst module to read input file as document

Refactor

- Update rst.py to add missing typing

Feat

- Add _parse_kv function to parse key-value pair
- Add _variable_type to parser to check type of variables

Fix

- Allow multiple character to variable type

Refactor

- Update _VARIABLE_PATTERN to add ignore pattern
- Update print format of argument_type_error in _pattern_type function
- Create constant for pattern of variable in parser
- Update pattern in _pattern_type function to allow all of char as input
- Change parsed values so that parser object have them

Feat

- Add cli module for this project
- Add appliaction module
- Update parser to set default value
- Add parser for cli