Fixed a problem with emitting block scalars (thanks to Andrey Somov): no longer emit indentation spaces when they are not needed; emit the correct number of leading breaks for folded scalars; emit the '+' chomping indicator for a single break scalar.
Fixed a problem with emitting block scalars (thanks to Andrey Somov): no longer emit indentation spaces when they are not needed; emit the correct number of leading breaks for folded scalars; emit the '+' chomping indicator for a single break scalar.

joannelynch92/pyyaml,joannelynch92/pyyaml