py-obspy: update compiler variants

[petrrr]

I updated compiler variant handling according to recipe: ​https://trac.macports.org/wiki/PortfileRecipes#fortran

This update should solves the following issues:

1. Commit r110107 broke this port as the port requires Fortran; I personally was not able to build with that commit. But even if it installs somewhere, it is very probably not functional.
2. The new compiler handling seems to have resolved some subtile issue/incompatibility for specific combinations of python26 and various gcc versions.

I therefore bump the revision number as well, because (a) it may have been installed from the nonfunctional version, (b) it solves the issue 2 and therefore should be updated/rebuild.

I tested under Mountain Lion with for Python 2.6 and 2.7, with all compilers except gcc49, which I cannot install due to conflicting libgcc.

Some doubt: Before the variants were available only for the subports. It was inside the if {${subport} != ${name}} block. However, it probably would make sense to have variants for the "superport" as well. This would than pass the variant to the default subport. Now, this constrain probably is present.

So how would this be implemented correctly?