split manpages into per-extension manpage snippet (Henrik Nordstrom)
add lots of missing manpage snippets (Harald Welte)
diff --git a/extensions/libipt_esp.man b/extensions/libipt_esp.man
new file mode 100644
index 0000000..7b84368
--- /dev/null
+++ b/extensions/libipt_esp.man
@@ -0,0 +1,3 @@
+This module matches the SPIs in ESP header of IPSec packets.
+.TP
+.BR "--espspi " "[!] \fIspi\fP[:\fIspi\fP]"