[giac] Changes related to support for interval arithmetic (requires MPFI), and solve/fsolve/proot/realroot/complexroot precision certification (PARI recommended for best performances with polynomials of degree about 100 or more).
A few improvements in system solving: e.g. solve([sqrt(x)+y=11,x+sqrt(y)=7],[x,y]) should now work

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@34072 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e