Changes:

  * Frame annotator interface folded into frame filters -- they are now
    all filters

  * Annotators renamed decorators

  * Guile module renamed (gdb frame-filters) from (gdb frames)

  * (ice-9 streams) streams instead of (srfi srfi-41) for pre-2.0.9
    compat

  * coding style foo

Thanks in advance for review :)

Andy