fix broken links

add robots file

fixing broken url

change landing page path

change url

Updated the @import for the theme css (NativeScript#1698)

The old one doesnt seem to work and the tilde one is whats listed on the https://docs.nativescript.org/ui/theme#color-schemes page.

Note the current bug in the CLI about template parsing

Version 2.4.0

Latest before version 2.4.0

Version 2.3.0