add svbhack responsive theme

svbhack is a svbtle inspired responsive theme for pelican, it does
not want to be a close copy but rather a svbtle-like theme; CSS is
rewritten completely, it also uses LESS and is rather lighweight

.gitmodules

@@ -43,3 +43,6 @@
 [submodule "irfan"]
 	path = irfan
 	url = https://github.com/erfaan/pelican-theme-irfan.git
+[submodule "svbhack"]
+	path = svbhack
+	url = git@github.com:giulivo/pelican-svbhack.git