Add Checks for Turtle and Pocket programs (#226)

Error if turtle and pocket computers programs are not run on
their respective devices.

src/main/resources/assets/computercraft/lua/rom/programs/pocket/equip.lua

@@ -1,3 +1,8 @@
+if not pocket then
+    printError( "Requires a Pocket Computer" )
+    return
+end
+
 local ok, err = pocket.equipBack()
 if not ok then
     printError( err )

src/main/resources/assets/computercraft/lua/rom/programs/pocket/unequip.lua

@@ -1,3 +1,8 @@
+if not pocket then
+    printError( "Requires a Pocket Computer" )
+    return
+end
+
 local ok, err = pocket.unequipBack()
 if not ok then
     printError( err )

src/main/resources/assets/computercraft/lua/rom/programs/turtle/craft.lua

@@ -1,3 +1,7 @@
+if not turtle then
+    printError( "Requires a Turtle" )
+    return
+end
 
 if not turtle.craft then
     print( "Requires a Crafty Turtle" )

src/main/resources/assets/computercraft/lua/rom/programs/turtle/dance.lua

@@ -1,3 +1,6 @@
+if not turtle then
+    printError( "Requires a Turtle" )
+end
 
 local tMoves = {
     function()

src/main/resources/assets/computercraft/lua/rom/programs/turtle/equip.lua

@@ -1,3 +1,7 @@
+if not turtle then
+    printError( "Requires a Turtle" )
+    return
+end
 
 local tArgs = { ... }
 local function printUsage()

src/main/resources/assets/computercraft/lua/rom/programs/turtle/excavate.lua

@@ -1,3 +1,7 @@
+if not turtle then
+    printError( "Requires a Turtle" )
+    return
+end
 
 local tArgs = { ... }
 if #tArgs ~= 1 then

src/main/resources/assets/computercraft/lua/rom/programs/turtle/go.lua

@@ -1,3 +1,8 @@
+if not turtle then
+    printError( "Requires a Turtle" )
+    return
+end
+
 local tArgs = { ... }
 if #tArgs < 1 then
     print( "Usage: go <direction> <distance>" )

src/main/resources/assets/computercraft/lua/rom/programs/turtle/refuel.lua

@@ -1,3 +1,7 @@
+if not turtle then
+    printError( "Requires a Turtle" )
+    return
+end
 
 local tArgs = { ... }
 local nLimit = 1

src/main/resources/assets/computercraft/lua/rom/programs/turtle/tunnel.lua

@@ -1,3 +1,7 @@
+if not turtle then
+    printError( "Requires a Turtle" )
+    return
+end
 
 local tArgs = { ... }
 if #tArgs ~= 1 then

src/main/resources/assets/computercraft/lua/rom/programs/turtle/turn.lua

@@ -1,3 +1,8 @@
+if not turtle then
+    printError( "Requires a Turtle" )
+    return
+end
+
 local tArgs = { ... }
 if #tArgs < 1 then
     print( "Usage: turn <direction> <turns>" )

src/main/resources/assets/computercraft/lua/rom/programs/turtle/unequip.lua

@@ -1,3 +1,7 @@
+if not turtle then
+    printError( "Requires a Turtle" )
+    return
+end
 
 local tArgs = { ... }
 local function printUsage()