Added the red dot (instead of the default `*`) if the branch is dirty.
The bira theme only supported git, now it supports mercurial as well. It
needed ito call `hg_prompt_info` and the `ZSH_THEME_HG_PROMPT_`
variables.
Closes#6631
Changes themes displaying RVM or other Ruby version info to use the central
ruby_prompt_info function. This supports more Ruby versioning mechanisms,
reduces copy-and-paste code, and avoids "zsh: no such file or directory: rvm-prompt"
when run on machines that do not have RVM installed.
Changes the prefix/suffix variable names to ZSH_THEME_RUBY_PROMPT_PREFIX and
ZSH_THEME_RUBY_PROMPT_SUFFIX, since they apply to all Ruby versioning mechanisms,
not just RVM.
Allows empty ZSH_THEME_RUBY_PROMPT_PREFIX and ZSH_THEME_RUBY_PROMPT_SUFFIX.
The whitespace in line 13 creates a double whitespace when combined with line 24. Therefore 2 whitespaces appear between ${user_host} and ${current_dir}.
