Specifying options in constraint and observable names

A new class QualifiedName was added to EOS, in order

• to centralize parsing of Constraint and Observable names, and
• to ensure that these names follow the correct syntax everywhere they are used.

Beside centralizing and reducing the code, in the process the syntax of these qualified names was changed in a backward-incompatible way. As of commit 348db60, a qualified name’s list of options is separated from the rest of the name by a ; character, e.g.: B->pipilnu::BR;model=CKMScan. The rationale for this change is that it makes the parsing a lot easier, and also allows for the usage of , characters in observable names. The latter is quite handy in order to distinguish between observables of the same basic name but varying dependence on kinematic variables. For example, we can now distinguish between three- and two-differential branching ratios ℬ(B → π π ℓ ν) through the names B->pipilnu::BR(q2,k2,cos(theta_pi)) and B->pipilnu::BR(q2,k2); see commit c897932. Also, the manual was updated and can be found in the usual place.

A big thank you to Rafael Silva Coutinho for help and discussions.