Enhancement - rc.name:value

- Supports 'rc.name:value' for a command line override to .taskrc data
  (thanks to Federico Hernandez).

ChangeLog

@@ -20,6 +20,8 @@
    Chris Pride).
  + Custom reports now support a more compact form of the "age" column,
    called "age_compact" (thanks to T. Charles Yun).
+ + Supports 'rc.name:value' for a command line override to .taskrc data
+   (thanks to Federico Hernandez).
  + Removed obsolete DEVELOPERS file.  The online support forums at
    http://taskwarrior.org will provide better information.
  + Replaced website references with http://taskwarrior.org.

src/Context.cpp

@@ -201,13 +201,11 @@ void Context::loadCorrectConfigFile ()
     if (arg->substr (0, 3) == "rc:")
     {
       std::string file = arg->substr (3, std::string::npos);
-      if (! access (file.c_str (), F_OK))
+      if (access (file.c_str (), F_OK))
-      {
-        config.load (file);
-        return;
-      }
-      else
         throw std::string ("Could not read configuration file '") + file + "'";
+
+      messages.push_back (std::string ("Using alternate .taskrc file ") + file); // TODO i18n
+      config.load (file);
     }
   }
 
@@ -221,8 +219,6 @@ void Context::loadCorrectConfigFile ()
   config.createDefault (file);
 
   // Apply overrides of type: "rc.name:value"
-/*
-  // TODO Maybe this should happen after the parse?
   foreach (arg, args)
   {
     if (arg->substr (0, 3) == "rc.")
@@ -237,10 +233,11 @@ void Context::loadCorrectConfigFile ()
           n.getUntilEOS (value))
       {
         config.set (name, value);
+        messages.push_back (std::string ("Configuration override ") +  // TODO i18n
+                           arg->substr (3, std::string::npos));
       }
     }
   }
-*/
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -258,7 +255,8 @@ void Context::parse ()
   {
     // Ignore any argument that is "rc:...", because that is the command line
     // specified rc file.
-    if (arg->substr (0, 3) != "rc:")
+    if (arg->substr (0, 3) != "rc:" ||
+        arg->substr (0, 3) != "rc.")
     {
       if (!terminated)
       {

src/task.cpp

@@ -265,7 +265,12 @@ static std::string longUsage ()
       << "  until:             Recurrence end date"                           << "\n"
       << "  fg:                Foreground color"                              << "\n"
       << "  bg:                Background color"                              << "\n"
-      << "  rc:                Alternate .taskrc file"                        << "\n"
+      <<                                                                         "\n"
+      << "The default .taskrc file can be overridden with:"                   << "\n"
+      << "  task rc:<alternate file> ..."                                     << "\n"
+      <<                                                                         "\n"
+      << "The values in .taskrc (or alternate) can be overridden with:"       << "\n"
+      << "  task ... rc.<name>:<value>"                                       << "\n"
       <<                                                                         "\n"
       << "Any command or attribute name may be abbreviated if still unique:"  << "\n"
       << "  task list project:Home"                                           << "\n"