factor out uncertainty calculations
copy headers to include dir for build

also, popped SpectralPlot into its own header, and various tweaks.
bring back fit plots
bring back contour uncertainties
Started clean up of config

Attempting to make it easier to create more complicated signal types
Moved random sampling code to pdfz class
Added the ability to build signals out of multiple pdfs
Now uses analytic time pdfs

It now expects pdfs for different fill fractions and will analytically
scale them and interpolate between them to allow a fit over time.
Added more time profiles, changed plotting
Added weighting to samples

Allows you to fit very high statistics signals by undersampling very
high statistics bins and then weighting those samples.
improve convergence by doubling the burn-in

Improve convergence by running two burn-in phases, adjusting the jump
distribution widths after each. This insulates the final run from a really
wrong initial jump distribution.

Also includes a few bug fixes.
Removed partialfill specific code
Merge remote-tracking branch 'mastbaum/cleanup' into partialfill

Conflicts:
	src/plots.cpp
	src/sxmc.cpp
Added ability to load data from ttrees