Fixed `n.children is undefined` when converting to LibCV and others

This fixed a bug that, if a source file happened to contain a childless code block, if would fail to convert to LibCV, Arduboy or ESP-LGE.
This fixes #15

Fix bug where the ESPBoy target wasn't displaying the dialogs

v0.11.1

Correct dialog display on LGE. Version 0.11.1

Implement support for ESPboy Little Game Engine

Implemented support for ESPboy Littlle Game Engine

Implement support for SDCC + LibCV

Now, the tool can also generate code for LibCV, meaning it can now be used to compile ROMs for:

• Colecovision;
• SG-1000;
• Sega Master System;
• MSX.

Refactor to simplify future implementations

• Create unit tests in order to ensure nothing breaks;
• Move data preprocessing to its own source file;
• Move C code generation to its own source file.

Title screen and endings.

Improvements on Arduboy code generation:

• Title screen implemented;
• Endings are now generated.

Exits are now functional

Improvements on Arduboy source generation:

• Exits implemented;
• Corrected a few bugs related to PROGMEM.

Animation and collision improvements

• Take into consideration whether a backgroud tile is solid or not when checking for collision;
• Tile animation is now working;
• Dialog strings are now stored on flash memory.

Collision detection and dialogs.

• Player now collides with the background;
• Player can interact with sprites;
• Only very simple dialogs are supported; no variables, nor conditionals.

Arduboy: movement and scrolling.

Additional Arduboy implementations:

• Player can now move around;
• Vertical scrolling implemented.