dsolve: Implement a general linear system solver
dsolve: Implement a general linear system solver

Uses Jordan form.

Edited by skirpichev.

Signed-off-by: Sergey B Kirpichev <6c6368f8f4cbabf33ffd2abfd270a2fcf839188a@gmail.com>

diofant/diofant,skirpichev/omg