Merge pull request #41 from learn-more/master

Sortable headers in serverbrowser
OpenAL doesn't have to be linked because it's linked at runtime
Merge branch 'master' of https://github.com/yvt/openspades
* Spade/block's reach fixed
Easier to place block under the feet
Faster dig (the same speed as the original AoS 0.75)
Changed version number to 0.0.8
GL_ARB_texture_non_power_of_two support is checked
Better system report
 * Max texture size is logged
 * Some of non-required extensions are shown
Added GL_MAX_TEXTURE_SIZE/GL_MAX_3D_TEXTURE_SIZE check
Shows other player's disconnection/joining a team
Improved error display
Disabled "reconnect without exiting" because it might cause a crash
Merge branch 'master' of https://github.com/yvt/openspades