added support for load(mext_core).
edited docs
	modified:   discrete_aex/number-functions.lisp
	new file:   mext_system/mext-core-user.lisp
	modified:   mext_system/mext.system
added nintegrate
	modified:   numerical/nintegrate.lisp
 small changes.
	modified:   defmfun1/defmfun1-max.lisp
 edit doc.
build nintegrate with the rest
fixed section for nintegrate
	modified:   numerical/ibuild.mac
rtests
	modified:   numerical/rtests/rtest_numerical.mac
reorganize
	modified:   numerical/README
	modified:   numerical/nintegrate.lisp
	modified:   numerical/rtests/rtest_numerical.mac
work on nintegrate
renamed a variable
added mext_list_loaded
worked on mext functions ,loading mext core...
	modified:   numerical/nintegrate.lisp
	modified:   numerical/rtests/rtest_numerical.mac
build numerical
	modified:   buildall.mac
	modified:   thirdparty.html
	modified:   thirdparty.pdf