v0.6.3

Coluna v0.6.3

Diff since v0.6.2

Merged pull requests:

• Stabilization for Column Generation (#930) (@guimarqu)
• Update NEWS.md & README.md (#946) (@guimarqu)
• Remove useless args in ColGen interface & fix stabilization (#948) (@guimarqu)
• Improve Column Generation generic functions (#949) (@guimarqu)
• Fix lagrangian bound calculation in column generation (#950) (@guimarqu)
• v0.6.3 (#951) (@guimarqu)