Update README.md

Added a Ternary operator section to Conditionals.
Update README.md

Fixed a spelling issue
Update README.md

Fixed the TOC Ternary Operator link
Added comments to the Table of Contents.
Add link to clarify the NARC acronym/mnemonic
Merge pull request #25 from jawwad/add-narc-link

Add link to clarify the NARC acronym/mnemonic
Greater explanation for conditional reasoning.
Tweaks to Brian's additions
Merge pull request #27 from NYTimes/one-line-conditionals

Deeper explanation for one-line conditional reasoning.
Added contributors.
Update README.md
Removed non-existent sections from the ToC.
Use `strong` instead of `retain` in code example
Merge pull request #31 from yas375/patch-1

Use `strong` instead of `retain` in code example
Update README.md

Updated the description for Ternary
Change i.e.'s to e.g.'s

i.e. means, essentially, "in other words." Use this to clarify meaning.

e.g. means "for example." Use this to provide an example (of many possible examples).

Signed-off-by: Andrew Phelps <andrew@phel.ps>
Fix commas

Signed-off-by: Andrew Phelps <andrew@phel.ps>
Remove space before link

Signed-off-by: Andrew Phelps <andrew@phel.ps>
Merge pull request #34 from phelps/master

Trivial copy edits
Merge pull request #19 from murdocdv/master

Add a section to Conditionals on the Ternary operator