Merge pull request #33 from gitcheng/master

Options in draw_ulh, draw_blh; analytical integral of HistogramPdf
Merge pull request #35 from gitcheng/master

Add BlindFunc to hide certain parameter's value
add return values from draw for custom drawing
Merge pull request #36 from piti118/plotdata

Add return values from draw for custom drawing
speed up blindfunc
Merge pull request #37 from piti118/blindfunc_speedup

speed up blindfunc
couple pep-8 and cdef
Merge pull request #38 from piti118/blindfunc_speedup

couple pep-8 and cdef
update change log for couple previous changes
Merge pull request #39 from piti118/integrate_perf

update change log for couple previous changes
Clean up the docs a bit
Update to tutorial.ipynb
Use minuit = Minuit() consistently
Use minuit = Minuit() consistently
Add comment about degenerate polynomial fit
fix typo
Clean up tutorial a bit

- no import *
- code formatting