Merge pull request #199 from mmklee/flintinterface_sw

Flintinterface sw
fix: lSize (from master)
Merge pull request #202 from mmklee/flintinterface_sw

fix: the right new extgcd res
chg: avoid undefined signed integer overflow
Merge pull request #204 from mmklee/factory_imm_mul_sw

chg: avoid undefined signed integer overflow
fix: idrCopyR need equal coeffs, fixed dim(i),dim(i,j) for ring-cf
fix: made local proc static, removed unsed variables (interpolation.cc)
Update on .gdbinit
Testing with -ftrapv
Temporary removed -Winline

TODO: revert this upon starting optimizing inline's
fix: naPower(0)
fix: avoid overflow somehow better
fix warnings: C++ comments in C code
fix: int overflow in hash function
fix: signed int overflow in nlMult
fix: int overflow in interpreter
fix: removed some unsed variables
fix: content in ivReduce
Added new experimental library "derham.lib"

add: derham.lib as an experimental library (SLIB1 in singular-libs)
add: added tests for derham.lib as Tst/Plural/derham.tst + included into Tst/Plural.lst
chg/fix: avoid "wrong weights" warning out of 'std'

TODO: induced deg seems to be ignored - one is to make use of "am" instead?
fix: bug_tr357 (configure for findexec:getpwnam)