This is an important refactor of the way documentation generation works

* Installs luarocks WITH it's executable (easy to install other rocks if necessary)
* Use Lua supplied with luarocks
* Create Utils/luadocumentor.bat, which works with RELATIVE PATH ! -> Everybody can generate the doc
* Updated launch files accordingly

Utils/luarocks/config-5.1.lua

@@ -0,0 +1,14 @@
+rocks_trees = {
+    home..[[/luarocks]],
+    { name = [[user]],
+         root    = home..[[/luarocks]],
+    },
+    { name = [[system]],
+         root    = [[C:/Users/Hugues/Documents/GitHub/MOOSE/Utils/luarocks\systree]],
+    },
+}
+variables = {
+    MSVCRT = 'MSVCR80',
+    LUALIB = 'lua5.1.lib'
+}
+verbose = false   -- set to 'true' to enable verbose output