Unify enum_name and enum_name_static
Expose toggle_prompt_name() as enum_name_prefixed()
Fix column option parsing by prefixing option names with the column name
Use status messages in the prompt code
Align relative dates to the right
Rewrite git color parsing to support multiple mappings per color
Use "--" as the separator in the grep view

This is what git uses and is less confusing than an empty line.
Parse color.grep.{filename,linenumber,separator} from git config
Fix documentation for the file color

And also remove documentation for the now obsolete tree-file and
tree-dir colors.
Introduce common header color
Introduce common section color
Add reflog member to the column_data struct

This way the ID width calculation does not have to guess if the ID is a
SHA1 or a reflog ID.
Unify jump-to-commit feature using the view ID column
Do not set diff-context option by default
Read git diff.context option