1) --with-max-am can be a list
2) 3-center ints are computed up to (LIBINT2_MAX_3ERI | LIBINT2_MAX_AM LIBINT2_MAX_AM) case, i.e. --with-eri3-max-am now specifies the angular momenta for the "auxiliary" center; the other centers use the value(s) given by --with-max-am

a bit more fragile than I like but necessary
minor tweaks of travis-ci config ... added google labels to the emails, etc.
Reverted the max angular momentum for ERI tests to the old value (non-derive ints up to l=3).
Libint_t::nflops is now a variable, not a ptr.
Minor tweaks.