Add hints to minibuffer

[svaante]

Inspired by joaotavora

Goals: Try to minimize read commands in buffers. Using dape--read-config as much as possible.

• Change dape-configs to use functions to generate default values rather then read.
• Add hints in dape--read-config to be able to display default values with the extra benefit of adding some clarity for long strings.
• Add ensure errors in minibuffer.
• New symbol property dape--minibuffer-hint if function is safe to be evaluate in any context.
• lambdas are shown as read in hint
• changes in jdtls config to be default first instead of read

With ensure error