rename a function to be more specific

This caused a bug in Lua Carousel. Scenario:
- Run carousel.love
- run the abbreviations screen which creates an abbreviation called `color`
- run driver.love

Before this commit, carousel.love would silently exit, and driver.love
would then hang waiting for it to come back. The cause:
- driver.love sends MANIFEST
- in processing it, carousel.love calls color() to emit a color escape.
- the error silently quits the app

After restarting carousel.love, the error shows up in driver.love:

  Error: live.lua:104: bad argument #3 to 'color' (number expected, got no value)
  stack traceback:
    [C]: in function 'color'
    live.lua:104: in function 'receive_from_driver'
    ...

live.lua

@@ -101,7 +101,7 @@ function live.receive_from_driver()
   local result = f:read('*a')
   f:close()
   if result == '' then return nil end  -- empty file == no message
-  print('<='..color(--[[bold]]1, --[[blue]]4))
+  print('<='..color_escape(--[[bold]]1, --[[blue]]4))
   print(result)
   print(reset_terminal())
   os.remove(love.filesystem.getAppdataDirectory()..'/_love_akkartik_driver_app')
@@ -113,7 +113,7 @@ function live.send_to_driver(msg)
   if f == nil then return end
   f:write(msg)
   f:close()
-  print('=>'..color(0, --[[green]]2))
+  print('=>'..color_escape(0, --[[green]]2))
   print(msg)
   print(reset_terminal())
 end
@@ -123,7 +123,7 @@ function live.send_run_time_error_to_driver(msg)
   if f == nil then return end
   f:write(msg)
   f:close()
-  print('=>'..color(0, --[[red]]1))
+  print('=>'..color_escape(0, --[[red]]1))
   print(msg)
   print(reset_terminal())
 end
@@ -131,7 +131,7 @@ end
 -- args:
 --   format: 0 for normal, 1 for bold
 --   color: 0-15
-function color(format, color)
+function color_escape(format, color)
   return ('\027[%d;%dm'):format(format, 30+color)
 end