True support for generic CSW servers

[amercader]

The CSW harvesters implemented at the moment were developed with the DGU project in mind, and they assume all remote CSW servers to implement the Gemini 2 specification. Gemini 2 is the profile defined in the UK for INSPIRE complying metadata, so obviously catalogs from other countries or non-INSPIRE complying ones won't be able to be harvested.

The changes needed to support generic CSW servers (i.e. those implementing the ISO 19139 profile) are:

• Handling the validators (right now are hardcoded in the harvester

code). This probably involves issues discussed in the CREP 3 (ticket #1134)

• Changes in the model to adapt the specification to ISO 19139

• Renaming objects and classes which are now Gemini-centric

List of CSW servers tested:

​https://spreadsheets.google.com/spreadsheet/ccc?key=0Atp3cZFjuIOAdDBVQWRINnlfN1d0b2lleHVEdjBSb2c&hl=en_US&authkey=CNu4hsEB#gid=0

[amercader]

Bumping to ckan-v1.5-sprint-3 and updating the CC email addresses so people actually get any updates.