To do list
* p-adics
#8685: evaluation of Monsky-Washnitzer objects (is really about power series over p-adics)
#11319: Cannot create homomorphism from prime residue field to finite field
* computing with chi_18
* p-adics
#8685: evaluation of Monsky-Washnitzer objects (is really about power series over p-adics)
#11319: Cannot create homomorphism from prime residue field to finite field
* computing with chi_18