extended Python API
moved includes
added palettes to returnable gdal datatypes. for the moment palettes can be max 255 entries but should be extended to 16-bits
new
inserted the color and color palette handling and restructured the code
added ods and xsls connectors
include for colors
added number of methods for support for colors
determinetype --> valuetype
rename from PrepareOptions to IOOptions
extended python api
Merge branch 'master' of https://github.com/52North/IlwisConnectors
Merge remote-tracking branch '52n/master' into feature/postgres-connector

Conflicts:
	spreadsheetconnectors/exceltableconnector.cpp
	spreadsheetconnectors/exceltableconnector.h
add log statement
refine database handling and provide workaround so that explorer can be instantiated with state