Add autocentering of overview

Work funded by Tuscany Region - SITA. Contract "Support to the use
of GFOSS (Geographic Free and Open Source Software) Desktop tools"
(CIG Z3B06FA6D7).
Add unit test for autocentering of overview

Work funded by Tuscany Region - SITA. Contract "Support to the use
of GFOSS (Geographic Free and Open Source Software) Desktop tools"
(CIG Z3B06FA6D7).
Add SIP and Python unit test for overview autocentering.

Work funded by Tuscany Region - SITA. Contract "Support to the use
of GFOSS (Geographic Free and Open Source Software) Desktop tools"
(CIG Z3B06FA6D7).
Fix overview autocentering: always center, not only when the overview is not visible.

Work funded by Tuscany Region - SITA. Contract "Support to the use
of GFOSS (Geographic Free and Open Source Software) Desktop tools"
(CIG Z3B06FA6D7).
Add an update of overview on centering mode switch
commit
Fix #6063
Fix #6063
[ftools] add warning for simplify tool when no one layer has been selected
Make sure updateFields() is called before setDisplayField for new vector layers (fix #8311)
Fix indexOf checks in setDisplayField, make sure they are case insensitive
[Plugin Installer] Remove hardcoded 2.0 version in order to use the native 2.0
translation update: es gl and ja
[dbmanager] another small fix for italian translation: fixes #8489
[pyqgis-console] add GEOS API file for autocompletion:
- add GDAL-1.10.0, QScintilla-2.7.2 api files
[dbmanager] Replace DropRasterTable func (deprecated) with DROP TABLE: fixes #8521
Merge pull request #853 from gioman/master

pt_PT translators list updated
translation update: danish by jacob
make alg work in modeller
translation update: german