[gatsby-theme-i18n] limit generation of localised pages to a subset of pages only

[olivier-lacroix]

Hello,

For some locales, I want to generate a localised page for only some pages. gatsby-theme-i18n currently does not allow that.

I imagine that:

• this could be parametrised by an array of RegExp whitelisting pages to localise in the config file;
• localizedPath would fallback to default locale when requesting a page that is not available in a given locale

Is this a feature you would consider including in gatsby-theme-i18n?

[olivier-lacroix]

I gave it a go in PR #133