Plot update 0.1.5

Changes since 0.1.3:

• The first meeting with Hinata's been rewritten.
• More plot, both at the beginning and the end (of the demo.)
• Assorted typo and grammar fixups.
• A bit more handholding for the player.
• More flavor options.
• Slight UI cleanup.
• Some fiddling around the choice to go outside.

Also, we don't have a Mac. If any Mac users would like to report on whether or not the Mac build works for them, please do.