v0.1.0: First public release with CI, tests, and example

Some noteworthy changes since last pre-release:

- Users can use arbitrary type for magnetic field with the minimal requirement
of defining a method `Vec3 MagneticField::ValueAt(Vec3 p) const`
- Converted some public types and functions to templates giving user more
flexibility
- Introduced new class for distortion calculations
  - Currently implemented distortion due to magentic field shape
- Cleaned up dEdx calculations for local TPC gain corrections. Also, cleaned up
coordinate transformations
- Covered by LGPL license due to borrowed code from the ROOT project