* Remove all dependencies of common code on doom/
    - net_client.c
 * Merge v_video.c to common version and delete duplicates
 * Merge r_draw.c to common version and delete duplicates
 * Merge ticcmd_t to common (needs netcode update)
 * Split d_iwad.c into common and use for Heretic/Hexen
 * Chocolate Setup to allow configuration for H/H
 * Remove duplicates:
    - Key definitions
    - Angles
    - Skill levels
    - Events
    - Endianness macros
    - i_system
    - argv
 * ENDOOM needs to be able to load ENDTEXT as well

Updates needed for Raven code:
 * Multiplayer code to use Chocolate Doom multiplayer code.
 * WAD code to use the new locking API
 * Config file code to use m_config.c (and add H/H-specific variables)
 * Use the common i_sound API.  Frequency shifting?
 * Video code to use screens[] - or dump screens[] and use a single variable
 * Use the common cheats code
 * Update input code to work properly with vanilla_keyboard_mapping
    
Clean up Raven code:
 * MAXINT -> INT_MAX, etc.
 * Check for endianness assumptions (shouldn't be too bad if it was developed
   on NeXT)
 * Savegame code to write structures predictably and endianness-correct
 * Remove NeXT and WATCOMC defines
 * Structure packing macros for structures read from disk