can this be solved with a plugin?

Author: logicplace

_includes/head-custom.html

@@ -0,0 +1,23 @@
+Jekyll::Hooks.register :pages, :pre_render do |page, payload|
+	INLINE_LINK_REGEX = %r!(\[(?:[^\[\]\\]|\\.|\g<1>)*\])\(\s*(/[^)\s]*)([^)]*?)\)!.freeze
+	REFERENCE_LINK_REGEX = %r!^\s*(\[(?:[^\[\]\\]*|\\.)+\]:) (/\S+)(.*)$!.freeze
+	LINK_REGEX = %r!#{INLINE_LINK_REGEX}|#{REFERENCE_LINK_REGEX}!.freeze
+
+	site = payload["site"]
+	baseurl = site.baseurl
+	page.content = page.content.gsub(LINK_REGEX) do |original|
+		matches = Regexp.last_match
+		inline_text = matches[1]   # [foo]
+		inline_url = matches[2]    # /bar
+		inline_title = matches[3]  #  "baz"
+		ref_tag = matches[4]       # [f]:
+		ref_url = matches[5]       # /bar
+		ref_title = matches[6]     #  "baz"
+
+		if inline_text
+			"#{inline_text}(/#{baseurl}#{inline_url}#{inline_title})"
+		else
+			"#{ref_tag} /#{baseurl}#{ref_url}#{ref_title}"
+		end
+	end
+end