refactoring: update relative paths in html templates when moving custom elements

[atsu85]

When i have a page and custom element files in one folder:

└───pages
        ig-register.html (custom element)
        ig-register.ts (custom element)
        register.html (page)
        register.ts (page)

I move them into subfolder

└───pages
    └───register
            ig-register.html
            ig-register.ts
            register.html
            register.ts

then relative paths in TypeScript file imports are updated correctly, but require tags should also be changed from

    <require from="../../../common/customElements/form/ig-input"></require>

to

    <require from="../../../../common/customElements/form/ig-input"></require>

[denofevil]

@atsu85 this should be covered by second part of #3, but let's keep it open so I won't forget to check