Enhancement - Aliases

- Moved alias mapping to Context.
- Added Context::canonicalize to resolve aliases.
- Added Context::loadAliases to reload on config file change.
- Removed old alias processing from Cmd.
- Doesn't work yet, but the data is loaded.

src/Context.h

@@ -65,8 +65,11 @@ public:
   void parse (std::vector <std::string>&, Cmd&, Task&, Sequence&, Subst&, Filter&);
   void clear ();
 
+  std::string canonicalize (const std::string&) const;
+
 private:
   void loadCorrectConfigFile ();
+  void loadAliases ();
   void autoFilter (Task&, Filter&);
 
 public:
@@ -81,7 +84,8 @@ public:
   std::string               program;
   std::vector <std::string> args;
   Cmd                       cmd;
-  std::vector <std::string> tagAdditions;  // TODO This is redundant, remove.
+  std::map <std::string, std::string> aliases;
+  std::vector <std::string> tagAdditions;
   std::vector <std::string> tagRemovals;
 
 private: