Support `.spool FilePath` command in CLI

[devgony]

To resolve #747

Goal

Spool is the easiest way to export data.

gluesql> .spool query.log
gluesql> VALUES (1), (2);
╭─────────╮
│ column1 │
╞═════════╡
│ 1       │
│ 2       │
╰─────────╯

gluesql> .spool off
gluesql> .quit

$> cat query.log
╭─────────╮
│ column1 │
╞═════════╡
│ 1       │
│ 2       │
╰─────────╯

Todo

• [x] Add Command::SpoolOn, CommandError::LackOfFile
• [x] Add Command::SpoolOff
• [x] if Some(spool_file), write to spool_file whenver print payload

Q

• Should we test the contents of created spool_file ?

In Next PR

Support granular options

• set header on | off
• set tabular on | off
• set echo on | off (show executed query or not)

[coveralls]

Pull Request Test Coverage Report for Build 2845690810

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.05%) to 97.896%

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Totals
Change from base Build 2833363350:	0.05%
Covered Lines:	29550
Relevant Lines:	30185

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💛 - Coveralls

[panarch]

Should we test the contents of created spool_file ?

It would be good to have one, but currently... it is not easy to make test based on rustyline. We may need to add test using internal function.