Add general support for region id
Add support for region id on eve-central fetcher
Fetcher query return empty array on error
Update phpdoc comment
Move updating on EVE items to its method
Dump duplicating of system based methods for region support
Ignore unset system and region ids
Simplyfing code.
Remove unused method and depending test
Revert "Remove unused method and depending test"

This reverts commit 81b06aa318bf877963b963d9b8579fb929dd41d3.
Remove unused method and non working test class.
Merge pull request #9 from henning-gerhardt/feature_region_support

Fix #5: Implementation of region support for market data.