FriCAS Code

generalize direct product

More reqular interface

Avoid division bu zero

Avoid overflow

Fix bug in freeMultiplicativeConvolution

Minor cleanups

bugfix representation optimization of IntegerMod

Before the patch, SingleInteger was also choosen as representation
for IntegerMod(p) if p was in the range m/2 < p <= m := max()$SingleInteger.

(1) -> I ==> SingleInteger
(2) -> p: I := max()$I - 123456

(2) 4611686018427264447
Type: SingleInteger
(3) -> a: I := p - 1

(3) 4611686018427264446
Type: SingleInteger
(4) -> a + a

>> System error:
The value
9223372036854528892
is not of type
FIXNUM

(4) -> addmod(a, a, p)

>> System error:
The value
9223372036854528892
is not of type
FIXNUM

rename axiom to fricas in code and documentation

AXIOM env variable --> FRICAS
AXIOMEDITOR --> FRICASEDITOR
AXIOMsys --> FRICASsys
axiom-wiki --> fricas-wiki
axiom --> fricas in message file s2-us.msgs
axiom-xl --> aldor
A# --> Aldor

The following changes require a newer Aldor compiler.
At least 13e5b90eecc79ec6704efb333c4c100187520e80 from 30-Jul-2019.
Before that the name libfricas was not treated correctly by Aldor.
libaxiom.al --> libfricas.al
axiom.as --> fricas.as

src/algebra/distro.spad: Typo in documentation

Remove unwanted documentation, add two new convolutions in DISTRO