improved error description when NTL is missing
Update cf_factor.cc

corrected spelling
chg: better assertions in factorize and deletion of SW_USE_NTL
chg: deleted SW_USE_NTL from cf_switches and misc_ip
chg: deleted SW_USE_NTL_GCD_*
chg: introduce cring
memset 0 the input to the signal handler. valgrind wasn't happy
add assumes to prevent accidental use of mor than 8 StringSetS or too
many StringEndS'es
chg: introduce cring
Merge branch 'spielwiese' of github.com:hannes14/Sources into spielwiese
fix: minbase does not work for rings as coefficient
Merge pull request #537 from mmklee/factory_emsg

Factory emsg
Merge commit '5b764351b565571d649b48901f5d83bdd8cf8e1' into spielwiese
(hopefully introduce cring)

Conflicts:
	Singular/misc_ip.cc
fix: syntax of debug version (factory/cf_factor.cc)
fix typo
Merge branch 'spielwiese' of github.com:Singular/Sources into spielwiese
format
Merge branch 'spielwiese' of github.com:Singular/Sources into spielwiese
add: Number/NUMBER2_CMD stuff: operations, conversions, print, string, ...
Add Anihilator to n_Z and n_Zn