v0.19.1

NLPModels v0.19.1

Diff since v0.19.0

Closed issues:

• Memory allocation in counters (#405)
• Fix docs (#409)

Merged pull requests:

• Spell out NLP (#410) (@PallHaraldsson)
• Up doc environment (#412) (@tmigot)
• sum_counters without allocations (#414) (@tmigot)
• Add in-place obj and grad! for nls (#417) (@tmigot)
• add FPS in breakage (#418) (@tmigot)
• Version 0.19.1 (#419) (@tmigot)