Default options changes

NOTE: Keep in mind that below changes are relative to Zandronum 3.0

• Default renderer is now OpenGL instead of Software.
• Default crosshair cvar value is now 2 instead of 0.
• Reduced default sound volume from 1.0 to 0.5.
• Reduced default music volume from 0.5 to 0.25.
• Reduced default menu volume from 0.6 to 0.3.
• Reduced default announcer volume from 1.0 to 0.5.
• Default m_noprescale cvar value is now OFF.
• Default gl_spriteclip cvar value is now 0 instead of 1.
• Default gl_billboard_mode cvar value is now 1 instead of 0.
• Default con_scaletext cvar value is now 1 instead of 0.
• Default cl_medals cvar value is now 0 instead of 1.
• Default autoaim cvar value is now 0 instead of 5000.