Log ctags version

autoload/tagbar.vim

@@ -1104,6 +1104,8 @@ function! s:CheckExCtagsVersion(output) abort
     call s:LogDebugMessage('Checking Exuberant Ctags version')
 
     if a:output =~ 'Exuberant Ctags Development'
+        call s:LogDebugMessage("Found development version, " .
+                             \ "assuming compatibility")
         return 1
     endif
 
@@ -1111,6 +1113,9 @@ function! s:CheckExCtagsVersion(output) abort
     let major     = matchlist[1]
     let minor     = matchlist[2]
 
+    call s:LogDebugMessage("Ctags version: " .
+                         \ "major='" . major . "', minor='" . minor . "'")
+
     return major >= 6 || (major == 5 && minor >= 5)
 endfunction