StationXML v0.2.0

Version 0.2.0 fully supports version 1.1 of the StationXML specification.

Breaking changes:

• All StationXML files which are written use version 1.1 of the spec.
• Minimum Julia version requirement upped to v1.2.

New features:

• Merging and appending of StationXML metadata

Improved functionality:

• Much improved IO speed
• Improved compatibility with real-world StationXML files
• Precompilation for faster loading