Verse text-alignment (and half-columns)

• Added Bootstrap's `text-center`, `text-left`, and `text-right` classes to `.verse`s.
• Added Bootstrap's `col-xs-6` and `col-xs-offset-6` classes to `.verse`s where the layout calls for positioning within the left or right half of the screen.
• Added `clear: both;` to the `.verse` CSS so that Bootstrap's columns never stack; each always gets its own line.
Tweak: Monologue line-height

• Added a `line-height` for .monologue text to be `1.8 * @font-size`.
	» Intended to stay the same even when a portion of text is larger (thus, a `px` size instead of just `1.8`).
	» Intended to be overridden as needed for larger text, or just wider spacing.
Added text-shadow to #ambitions-phase content

• Added the same `text-shadow` #sky-phase uses to #ambitions-phase— 3px spread, 25% black.
• Minor: Changed #ambitions-phase's color from `white` to `#fff`.
	» Hex rulez.