Bump version to 0.18

This is release is mostly just to get libefiboot api out there where it
cna be used.

0.19 will be mostly documentation for efiboot and verification that more
obscure device types (nvme, ib, iscsi, fc, fcoe) path generation works.

Signed-off-by: Peter Jones <pjones@redhat.com>

Makefile

@@ -1,7 +1,7 @@
 TOPDIR = $(shell echo $$PWD)
 
 SUBDIRS := src docs
-VERSION := 0.17
+VERSION := 0.18
 
 all : $(SUBDIRS) efivar.spec