chg: doc. for #432 (cntrlc handling)
fix: tr #442: % and mod are now the same, result is non-negative

from master
add: type conversion for bigint
add: doc for type conversion: list -> ring
fix: description of ordering rp
fix: typo (#467)
chg: MP links -> ssi links
tag more examples

Add a way to tag all examples from a .lib file included.

Use this new feature to tag some libs needed external programs,
special features or significant memory usage in order to be able
to build documentation on more machines.

Make DOC2TEX_EXAMPLE_EXCLUSIONS a make variable, so that this
setting can also be overridden at make invocation time.
chg: MP links -> ssi links