Fix draw_blh
fix #31 wrong polynomial integral
Merge pull request #32 from piti118/fix31

fix #31 wrong polynomial integral
add Changelog
Fix draw_blh normalization.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	probfit/_libstat.c
	probfit/costfunc.c
	probfit/functor.c
	probfit/funcutil.c
	probfit/pdf.c