Version 0.1.2

This is a bug-fixing patch that addresses a few outstanding build issues,
targeted at making it easier to run and debug the regression problem suite.

New features

• Save JSON exception output if demo loop fails by @sethrj in #507

Bug fixes

• Fix class name conflict, remove default initializers, and tweak field driver @sethrj in #504
• Fix no-ROOT demo loop for 0.1.x and other summit changes by @sethrj in #508

Full Changelog: v0.1.1...v0.1.2