Update instructions for developers.

- Some of them were get from bitmask_client docs.

This closes #4185.
Update databases list, add tapicero to misc
Create tapicero.md

Copy tapiceros readme into leap_doc.
Add tapicero to menu
Add database setup section to overview

Explaining setup of 'normal' and per-user databases. link to tapicero, point out where the design docs come from and where they go.
Emphazise usage within leap platform for tapicero

Sorting the sections so the usage scenarios for the platform come first.
Corretions and update to pt-br translation.
More correcions in pt-br translation.
Fix typ0 on pt-br translation.
add link to list archives
fix link(?)
Mac OS X 10.9 Requeriments section
Added OX 10.9 to working combinations.
Fix typo?

The node created was named web1.
added secure email report.
added services <> node type table.
expanded the key validation problem to be a general 'key management problem'
added brief mention of ZRTP
pull secure-email from upstream
refreshed secure-email from upstream