Add new massDependences and expansions

[fkrinner]

Mass dependences:

• Polynomial
• Fourier mode
• Sawtooth
• Arbitrary TFormula

Expansions:

• Taylor
• Fourier
• Chebyshev
• Sawtooth (no extra code was necessary for this, works automatically with the new sawtooth mass-dependence and the old bin-expansion)

[suhlatwork]

Could you please check suhlatwork/ROOTPWA@d9728c1dca8b7fc0d5eb3c59661a7c60460a0cff? Mostly my changes are cosmetic, but:

• classes from boost that have a C++11 counterpart need the explicit boost:: namespace (shared_ptr, tuples, ...)
• the mMin and mMax parameters have been moved out of the fourier and chebyshev expansions as they are not used in the expansion itself

I still see potential issues with

• the arbitrary mass dependence has a non working example. Formulas may not contain the / character (and probably others) as they are interpreted as a directory. I think this should be removed entirely
• the three new expansions: If I remember correctly we decided at the time of adding the expansions that the name variable inside the expansion was supposed to be the variable that is added instead of the expand.

[suhlatwork]

The commit you just added (5701792) is already included in master.

[fkrinner]

Did not intend to, sorry. Thanks for noticing.