style(core): make code formatting more consistent and legible

Request Type: style

How to reproduce:

Component(s): core

Impact: small

Complexity: small

This issue is related to:

**Detailed Description:**
This commit changes the code formatting of the Angular.js core to adhere more closely to Google's JavaScript style guide. This includes adding whitespace and blank lines where needed. It also removes some unused variables, while renaming others to provide more clarity as to what it does (e.g. `ii` to `attributePrefixLength`).

**Other Comments:**