Comment 0 for bug 1169876

GOAL
Add historical catalogue as usable layer in oq-platform eco-system and an application to explore it.

OPEN ISSUES
  - the original CSV file don't use UTF8 charset and we identify it as iso8 or iso15 but we are waiting for a clarification or a new native UTF8 file.

STYLE
The proposal for layer style includes:
  - Magnitude: item dimension
  - Magnitude Type: item shape
  - Depth: full saturation colors (gray for unknown)