made build.sh generate documentation, updated vt-task docs

build.sh

@@ -6,3 +6,4 @@ echo _OSVERSION=\"PsychOS 2.0a1-$(git rev-parse --short HEAD)\" > target/version
 cat target/version.lua target/init.lua > target/tinit.lua
 mv target/tinit.lua target/init.lua
 cp -r exec/ service/ lib/ target/
+lua finddesc.lua $(find module/ -type f) $(find lib/ -type f) > apidoc.md

module/vt-task.lua

@@ -1,6 +1,6 @@
 do
 --#include "module/vt100.lua"
-function vtemu(gpua,scra)
+function vtemu(gpua,scra) -- creates a process to handle the GPU and screen address combination *gpua*/*scra*. Returns read, write and "close" functions.
  local gpu = component.proxy(gpua)
  gpu.bind(scra)
  local write = vt100emu(gpu)