HUD bar

[cxong]

After the changes in #515, the HUD can look ugly when the elements are inconsistently hidden.
The HUD should be redesigned. Mockups have shown that the best design is a horizontal bar - this introduces minimal clutter while still showing the elements adequately - especially the gauges.

The redesigned HUD has (left to right)

• Player icon, rendered exactly the same as the real player, to help players instantly recognise themselves
• Combination name and health bar; this is deliberately long because the longest names can be up to 20 characters long. However, this could be condensed given a name abbreviation function
• Number of lives
• Gun and ammo icon
• Combination reload and ammo gauge
• Grenades
• Score/cash

Implementing this can be done in stages:

• Lay out existing elements in a bar
• Add ammo icon
• Add bar graphic
• Add player icon
• Improved bar edge graphics, bar background, possible animated background etc.

[cxong]