Fix logo on subpages

Signed-off-by: Rafal Kupiec <belliash@codingworkshop.eu.org>

themes/exectos/layouts/partials/header.html

@@ -1,6 +1,6 @@
 <div class="wrapper_header">
 	<div class="header">
-		<h1><a href="{{ .Site.BaseURL }}"><img src="images/exectos_logo.png" alt="LOGO" width="50px" /> {{ .Site.Title }}</a></h1>
+		<h1><a href="{{ .Site.BaseURL }}"><img src="/images/exectos_logo.png" alt="LOGO" width="50px" /> {{ .Site.Title }}</a></h1>
 		<ul>
 			{{ range .Site.Menus.main }}
 			{{ if .HasChildren }}