feat: customization options

[paulwer]

hey folks, while developing this theme suiteable for our company, we had address some minor responsive issues and placed a background video + our own logo at the top-left corner. which looks quite neat.😇

as this could be a good additional option to customize the theme easily i would like to introduce a customization behavior by the theme.properties file, so anyone can just paste theire sources in and are good to go.

@lukin is this something you would like to see or would such behaviors be to tough to support in the future? if this is not wanted for the future, its ok if you just close the PR. <3

https://github.com/lukin/keywind/assets/52678724/2ec5fa7e-d7f6-4e7c-ab6c-25bfb82266b2

[paulwer]

if this pr gets merged, i would also introduce our gdpr/ccpa compliant solution for the footer: (or in germany: dsgvo)

• display impress link with translation
• display data security link with translation
• cookie consent by https://www.github.com/orestbida/cookieconsent (which uses #53)

customization options, could also be usefull for the logo within the comming email theme, to dont require the user to change it within the file.

[paulwer]

@lukin thanks for updating the PR. Happy to hear, such feature is wanted?

If you interested, I can also add the footer thing mentioned above. If wanted, which languages should be used? We currently use: eng, ger, it, fr, ru

Displayed with plain if statements. Do you know a better option to may use and/or extend localization?

[paulwer]

closed in favor for: https://github.com/lukin/keywind/pull/96