Integer factoring improvements

[roed314]

This patch adds methods for factoring integers of the form b^k + 1

Depends on #7240
Depends on #12117
Depends on #12133

CC: @jdemeyer @JohnCremona @sagetrac-ylchapuy @jpflori @rwst

Component: factorization

Author: David Roe

Issue created by migration from https://trac.sagemath.org/ticket/12125

[roed314]

comment:3

Updated against 5.8.beta0

[jdemeyer]

comment:4

Attachment: 12125.patch.gz

[rwst]

comment:8

Cannot be reviewed until #15813 has seen work and is closed.