fix for left nav tabs
Merge pull request #777 from twokul/fix-for-left-nav-tabs

fix for left nav tabs
fix typo in getting started guide
Merge pull request #778 from jaimeiniesta/patch-1

fix typo in getting started guide
fix typo on accepting-edits.md
fix another typo on accepting-edits.md
Merge pull request #780 from jaimeiniesta/patch-2

fix another typo on accepting-edits.md
Merge pull request #779 from jaimeiniesta/patch-1

fix typo on accepting-edits.md
update state manager docs
Ember Data doc updates
Add ember data core concepts
Add architecture overview for ember data
Store and finding records docs
Add application template cross-reference
Guide <ul>s should use a disc
Tons more ember data docs
Wordsmithing
Update defining-models.md with typo

changed "bed" to "best" under Explicit Inverses
Update defining-models.md be consistent with capitalization of Attr types

SHould these be titlecased or lower case?
`string`, `number`, `boolean`, and `date`.

Here they are Capitalized but in 
CREATING CUSTOM TRANSFORMATIONS
section they are lower case.
Better explain pushing vs. requesting