Document new scripts

scripts/migrants-now.lua

@@ -1,2 +1,11 @@
 -- Force a migrant wave (only works after hardcoded waves)
 --@alias = 'devel/migrants-now'
+--[[=begin
+
+migrants-now
+============
+Forces an immediate migrant wave.  Only works after migrants have
+arrived naturally.  Alias for ``devel/migrants-now``; equivalent to
+`modtools/force` ``-eventType migrants``
+
+=end]]

scripts/spawnunit.lua

@@ -1,5 +1,13 @@
 -- create unit at pointer or given location
 -- wraps modtools/create-unit.lua
+--[[=begin
+
+spawnunit
+=========
+``spawnunit RACE CASTE`` creates a unit of the given race and caste at the cursor, by
+wrapping `modtools/create-unit`.  Run ``spawnunit help`` for more options.
+
+=end]]
 
 usage = [[Usage:
 - spawnunit RACE CASTE