[samples] fixes and tuning of some samples

* add splash in a few samples
* fix clone example (showing firefox info by default in chrome...)
* clearer svg message (for unspecified width/height)
[includedeck] add profile-2-fitnofs for samples
[incubator] remove loading.(s)css (deprecated by updated new core)
[smartsyntax] reindent part of the code
[step] add a 'z' key to step to the end of the current/next toplevel (to navigate decks with lot of incremental stuff)
[clone] fixed pointer replication with subslides (depends on the step extension for convenience)