[Context Manager ] Ability to copy an application context from the context manager UI

[catmorales]

Description

Create a new context from the manager by cloning an existing one.
The functionnality changes the copied context's name, the URL and could initialize the contexts rights but keeps the properties of the source context:

• map,
• map templates,
• plugins and their personnalized configuration,
• theme configuration

What kind of improvement you want to add? (check one with "x", remove the others)

• Minor changes to existing features
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Mapstore2georchestra improvement
• Mapstore2 improvement
• Other... Please describe:

Other useful information