[FEATURE] Add more presets and initializer for PageSize about unipdf

[sampila]

Hi @Shion1305,

Thanks for the suggestions, we will considering your feedback.
Currently to sets the custom page size should be easy, like if you want to set the page size to US Standard: 3.5inchx2inch, you can follow this line of code below

c := creator.New()

...
pageSizeUSStrandard := creator.PageSize{3.5 * creator.PPI, 2 * creator.PPI}

c.SetPageSize(pageSizeUSStrandard)

Our API references can be seen on https://apidocs.unidoc.io/unipdf/v3.39.0

Best regards,
Alip

[github-actions]

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