Add new step on wizard.
Add wizard_dialog_base.py to Makefile and compile it.
Change object name.
Set max value and step of combo box.
Almost done, needs codes for behaviour.
Add behaviour for wizard.
Pep8.
Elderly to elder.
Merge with origin/develop.
Add description for units.
for #980
Merge with inasafe/develop.
Add translations for #959. Verified that the translations appear in UI.
For tooltip on source stepd due to #961.
Tim's review.
Fix typo.
Fix tooltips.
Put icon on top, text on below.
Merge remote-tracking branch 'origin/develop' into fix_wizard
PEP8.