Login Response support for destination_guide_url, OpenSimExtras support (properly) search-server-url, and support the new destination-guide-url from OpenSimExtras

Expands SignaledType's callback to accept const Type& as argument.
typedefs Signal::slot_type to slot_t so that SignaledType can be altered without needing to update all lines setting slots.

Merges floater_directory.xml with floater_directory(2|3).xml
Condenses translations down to one xml(, finally the nightmare is over).
Better ui code support for classic find all panel
Not like anyone cares, but ShowcaseURLDefault no longer persists value changes between sessions.

Moves SearchType and getSearchUrl(SearchType ty, bool is_web) from HippoGridInfo into a namespace in llpaneldirfind.cpp, the only place where it is used; so that it may wrap the sim feature lookup.

Thanks to Shyotl for the help in dynamically maintaining tab positions for dynamic tabs.

indra/newview/hippogridmanager.h

@@ -31,11 +31,6 @@ public:
 		PLATFORM_SECONDLIFE,
 		PLATFORM_LAST
 	};
-	enum SearchType {
-		SEARCH_ALL_EMPTY,
-		SEARCH_ALL_QUERY,
-		SEARCH_ALL_TEMPLATE
-	};
 
 	explicit HippoGridInfo(const std::string& gridName);
 
@@ -58,7 +53,6 @@ public:
 	const std::string& getSearchUrl()       const { return mSearchUrl; }
 	const std::string& getGridMessage()     const { return mGridMessage; }
 	const std::string& getVoiceConnector()  const { return mVoiceConnector; }
-	std::string getSearchUrl(SearchType ty, bool is_web) const;
 	bool isRenderCompat()                   const { return mRenderCompat; }
 	std::string getGridNick() const;
 	int getMaxAgentGroups() const { return mMaxAgentGroups; }