improve nuvla documentation

[cjdcordeiro]

• Nuvla Production Installation is still too long, cumbersome and hard to follow (@0xbase12)
• "customize-apps" is too cumbersome and decoupled from everything else. I'm not sure it is worth having in there. If you want to keep it, maybe consider moving it to the tutorials page (@0xbase12)
• Move all "Hands-on Exercises" into a 1st level section called "Tutorials" (@cjdcordeiro)
• CaaS Infrastructures are also too hard to follow, and introduce too many concepts that we shouldn't be explaining to a user. Links and references to external docs are preferred. This section must be simplified (@0xbase12)
• "Manage Data" Demonstration for Emma...not sure if it fits there. Maybe move to the "Tutorials" sections, as "Demonstrations" (@konstan)
• same for the "Running Applications with Data" Alice demonstration (@cjdcordeiro)
• for Felix, add the procedures for contributing to Nuvla* (@mebster)
• add demonstration for the NuvlaBox video demo (@cjdcordeiro)

[cjdcordeiro]

I'm not sure how to re-write this one: http://docs.nuvla.io/nuvla/customize-apps

[cjdcordeiro]

Tutorials section: #24

[cjdcordeiro]

shall we also add support@sixsq.com somewhere ? Maybe on the bottom of the navbar, above the copyright...

[cjdcordeiro]

@0xbase12 @konstan @mebster I'm taking myself out as I don't have any other bullets to complete. Please keep updating this

[cjdcordeiro]

@0xbase12 @mebster please double check whether the missing boxes are still unticked

[mebster]

I've fixed the one for Felix.

[mebster]

@konstan could you look at the CaaS one? With the latest machine feature, should this not be updated/re-written?