[build] staticly link libstdc++ and libgcc
[build] staticly link libstdc++ and libgcc

This hopefully gives our binary better chances of "just working"
on slightly different linux versions.  Our direct shared library
dependencies are pretty minimal:

$ readelf -a out/traceviz  | grep NEEDED
 0x0000000000000001 (NEEDED)  Shared library: [libSDL2-2.0.so.0]
 0x0000000000000001 (NEEDED)  Shared library: [libGL.so.1]
 0x0000000000000001 (NEEDED)  Shared library: [libdl.so.2]
 0x0000000000000001 (NEEDED)  Shared library: [libm.so.6]
 0x0000000000000001 (NEEDED)  Shared library: [libc.so.6]
 0x0000000000000001 (NEEDED)  Shared library: [ld-linux-x86-64.so.2]

swetland/traceviz,swetland/traceviz