AT 2.6

Main changes

• First release under the Apache 2.0 license
• Lattices may be loaded and saved in JSON format. AT files in JSON format can be used for exchanging lattices between Matlab and python, as an alternative to the proprietary .mat format.

New features

• AT Licensing by @lfarv in #760
• Save and load lattices in JSON format by @lfarv in #766

Bug fixes

• Update atsimplering in Matlab by @lfarv in #719
• Atavedata by @ZeusMarti in #678
• Bug in piwinski touschek scattering B2 term by @swhite2401 in #765
• Fix a regression bug in atavedata by @lfarv in #774

Full Changelog: 2.5...2.6