Git: Conditionally enable Reset button in branches dialog

Conditions:
* There is an active local branch
* The selected node is a leaf
* The selected node is not the active branch

Change-Id: I539dd13750737934378e503484646634e50a1aa7
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>

src/plugins/git/branchdialog.cpp

@@ -128,6 +128,7 @@ void BranchDialog::enableButtons()
     m_ui->diffButton->setEnabled(hasActions);
     m_ui->checkoutButton->setEnabled(hasActions && !currentSelected);
     m_ui->rebaseButton->setEnabled(hasActions && !currentSelected);
+    m_ui->resetButton->setEnabled(hasActions && currentLocal && !currentSelected);
     m_ui->mergeButton->setEnabled(hasActions && !currentSelected);
     m_ui->cherryPickButton->setEnabled(hasActions && !currentSelected);
     m_ui->trackButton->setEnabled(hasActions && currentLocal && !currentSelected && !isTag);