[feat] 增加 TD test 以及 ledger 后端增加 tag 的支持

[ramsayleung]

Description

1. double-entry-generator 增加 TD provider 的 End-to-End test.
   • 增加 test/test-td-{ledger,beancount}.sh 文件
   • 更新 example/td/example-td-output.beancount 文件, 原来文件直接 copy 自 ledger 文件.
2. ledger 后端增加 metatag 的支持
   • 单个tag 语法为: ; :tag1:
   • 多个tag 语法为: ; :tag1:tag2:

Motivation and Context

#101

Dependencies

None

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How has this been tested?

End-to-End test

• [x]: td-test-ledger.sh: pass
• [x]: td-test-beancount.sh: pass
• [x]: make test: pass

metatag test

ledger -f ./example/td/example-td-output.ledger --limit 'has_tag(/cheap_tag2/)' reg, 返回结果符合预期:

ledger -f ./example/td/example-td-output.ledger --limit 'has_tag(/tt_tag/)' reg, 返回结果符合预期:

Is this change properly documented?

Please make sure you've properly documented the changes you're making.

Don't forget to add an entry to the CHANGELOG/README if necessary (new features, breaking changes, relevant internal improvements).

Yes, we need to update the README, I would submit a new PR to update README once everything is done.

[Triple-Z]

LGTM