 No possible compile with GCC as part of application (Ubuntu)
I tried to compile game with GLAD as part of application, but I seen this error. 

```
Will make a "devel" build of Neverball 1.6.0-77-e42fc85+.
cc -Wall -Wshadow -std=c99 -pedantic -O2 -o neverball glad/glad.o share/lang.o share/st_common.o share/vec3.o share/base_image.o share/image.o share/solid_base.o share/solid_vary.o share/solid_draw.o share/solid_all.o share/mtrl.o share/part.o share/geom.o share/ball.o share/gui.o share/font.o share/theme.o share/base_config.o share/config.o share/video.o share/glext.o share/binary.o share/state.o share/audio.o share/text.o share/common.o share/list.o share/queue.o share/cmd.o share/array.o share/dir.o share/fbo.o share/glsl.o share/fs_common.o share/fs_png.o share/fs_jpg.o share/fs_rwops.o share/fs_ov.o share/log.o ball/hud.o ball/game_common.o ball/game_client.o ball/game_server.o ball/game_proxy.o ball/game_draw.o ball/score.o ball/level.o ball/progress.o ball/set.o ball/demo.o ball/demo_dir.o ball/util.o ball/st_conf.o ball/st_demo.o ball/st_save.o ball/st_goal.o ball/st_fail.o ball/st_done.o ball/st_level.o ball/st_over.o ball/st_play.o ball/st_set.o ball/st_start.o ball/st_title.o ball/st_help.o ball/st_name.o ball/st_shared.o ball/st_pause.o ball/st_ball.o ball/main.o share/solid_sim_sol.o share/fs_physfs.o share/tilt_null.o share/hmd_null.o     -lSDL2_ttf -lvorbisfile -L/usr/lib/x86_64-linux-gnu -lSDL2 -lGL -ljpeg -lpng16 -lphysfs -lm
/usr/bin/ld: glad/glad.o: undefined reference to symbol 'dlclose@@GLIBC_2.2.5'
//lib/x86_64-linux-gnu/libdl.so.2: error adding symbols: DSO missing from command line
```

Too many letters, but I can say that generated GLAD is incompatible with Linux compilers. 