Added bira theme (based on ZSH bira theme)

themes/bira/fish_prompt.fish

@@ -0,0 +1,43 @@
+# Theme based on Bira theme from oh-my-zsh: https://github.com/robbyrussell/oh-my-zsh/blob/master/themes/bira.zsh-theme
+# Some code stolen from oh-my-fish clearance theme: https://github.com/bpinto/oh-my-fish/blob/master/themes/clearance/
+
+function __user_host
+  echo -n (set_color --bold green)$USER@(hostname|cut -d . -f 1) (set color normal)
+end
+
+function __current_path
+  echo -n (set_color --bold blue) (pwd) (set_color normal) 
+end
+
+function _git_branch_name
+  echo (command git symbolic-ref HEAD ^/dev/null | sed -e 's|^refs/heads/||')
+end
+
+function _git_is_dirty
+  echo (command git status -s --ignore-submodules=dirty ^/dev/null)
+end
+
+function __git_status
+  if [ (_git_branch_name) ]
+    set -l git_branch (_git_branch_name)
+
+    if [ (_git_is_dirty) ]
+      set git_info '<'$git_branch"*"'>'
+    else
+      set git_info '<'$git_branch'>'
+    end
+
+    echo -n (set_color yellow) $git_info (set_color normal) 
+  end
+end
+
+function fish_prompt
+  set -l white (set_color white)
+  
+  echo -n (set_color white)"╭─"(set_color normal)
+  __user_host
+  __current_path
+  __git_status
+  echo -e ''
+  echo (set_color white)"╰─"(set_color --bold white)"\$ "(set_color normal)
+end