fix GDAL path defaults for OS X
wms provider: add trailing slash, if url path is empty otherwise and clear tileset list, when a tileless wms server is connected
oracle provider: add context help
german translation update
Replaced one occurence of "on database" with "in database"
[FEATURE] Load and Save SLD & QML styles to DB
Replaced last occurence of "on database" with "in database"
Solved an issue loading the default style adding a layer
Work done for ARPA Piemonte - Dipartimento Tematico Geologia e Dissesto
Ask for confirmation before overwrite a layer style
Solved errors made using diff tool in last merge
reapply some cleanup to 'styles_to_db'
Fixed bug processing URL parameters
Add support page link.
Load online help manual from help menu
Disable blend modes when printing or pdf exporting as vector, prevents missing composer items in output
Merge pull request #583 from ccrook/delimited_text_bug_fixes_3

Fixed bug processing URL parameters
Update labeling gui and add expression support as data defined value

- Add QgsDataDefined class
- Add QgsDataDefinedButton class
- Add standalone SVG selector dialog to QgsSvgSelectorWidget class