celx: add titles for examples

scripts/eclipticgrid.celx

@@ -1,3 +1,5 @@
+-- Title: Toggle Eclipic Grid
+
 t = {} -- create table
 t.equatorialgrid = 	false
 t.galacticgrid = 	false

scripts/galacticgrid.celx

@@ -1,3 +1,5 @@
+-- Title: Toggle Galactic Grid
+
 t = {} -- create table
 t.equatorialgrid = 	false
 t.galacticgrid = 	not celestia:getrenderflags().galacticgrid

scripts/horizontalgrid.celx

@@ -1,3 +1,5 @@
+-- Title: Toggle Horizontal Grid
+
 t = {} -- create table
 t.equatorialgrid = 	false
 t.galacticgrid = 	false

scripts/marktype.celx

@@ -1,3 +1,5 @@
+-- Title: Mark all D stars
+
 function mark_spectraltype(x)
     local obs = celestia:getobserver()
     local nstars = celestia:getstarcount()

scripts/tour-system.celx

@@ -1,3 +1,5 @@
+-- Title: Tour around Solar system objects
+
 function gotoobject(o, t)
     local obs = celestia:getobserver()
     obs:follow(o)