Update git-ignored files
Omit PyXB "Unable to convert DOM node to binding" warnings in RPM req/prov generators

These warnings are generally harmless, but logs are full of them and
people are asking about them.
[logging] Add forgotten license header
[maven.req] Avoid KeyError exception when dealing with config file
Print some debug information in maven req/prov generators
[maven.req] Print debug info about POM dependencies
[osgi.req] Refactoring
[osgi.req] Print debug information
[osgi.req] Fix "TypeError: not all arguments converted during string formatting"
[osgi.req] Print debug information only if set of RPM requires is not empty
[maven.prov] Fix "NameError: name 'privides' is not defined"
[osgi.prov] Refactoring
[osgi.prov] Add logging
[osgi.prov] Try to print provides only if there are some
[pyxbmetadata] Regenerate bindings with PyXB 1.2.4
[pom_editor] Fix missing space between xmlns declarations
[pom_editor] Simplify make_path to make it more future-proof

There was a complicated expression that compared truthiness of etree element,
which may differ among versions. Simplified and disambiguated.
[pom_editor] XPath errors don't always have message
Prevent warnings from PyXB about missing logger handler

This silences warning:

    No handlers could be found for logger "pyxb.binding.basis"