Squirrel - data access infrastructure

Prompt seismological data access with a fluffy tail.

• Squirrel API usage
  • Variant 1: quick and dirty script
  • Variant 2: command line app (simple)
  • Variant 3a: command line app (tight integration, single-command)
  • Variant 3b: command line app (tight intergation, multi-command)
  • Variant 4: command line app (loose integration)