New admin reorganization

[zarvox]

• Adds a root admin panel page
• Divides admin panel pages into Configuration (server settings) and Management (day-to-day operational task support).
• Moves to breadcrumb-based hierarchical navigation for individual admin pages (which works very nicely for e.g. Admin / Users / Invite)
• Corrects a good deal of inconsistent capitalization in the product. The standard we (attempt to) follow is to capitalize the first letter of a heading, label, or button, but no other words, unless they are proper nouns. For example, "Sandstorm for Work" and "Sandstorm" are always capitalized as written here.
  • I don't think "Trash" and "Main list" qualify as proper nouns.
  • App market is not a proper noun when we write it on our blog, so I assumed it needn't be here either.
  • I didn't bother fixing capitalization in the old admin panel since I intend to deprecate/remove it Soon™.

[paulproteus]

I a​dded some of this info here: https://github.com/sandstorm-io/sandstorm/wiki/English-language-style-guide Feel free to expand/correct etc., but I figure we should make sure this info lives somewhere so that when we are wondering what the standard is, we have a place to look.

[paulproteus]

Also wow, this is great, looking at the screenshots.