various: encapsulate all code in the olive namespace to avoid name collisions

Large-scale code cleanup. Also adds a license to the top of all files that were
missing it.

app/render/backend/indexmanager.cpp

@@ -1,12 +1,30 @@
+/***
+
+  Olive - Non-Linear Video Editor
+  Copyright (C) 2019 Olive Team
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+***/
+
 #include "indexmanager.h"
 
 #include "task/taskmanager.h"
 
-IndexManager* IndexManager::instance_ = nullptr;
+OLIVE_NAMESPACE_ENTER
 
-IndexManager::IndexManager()
-{
-}
+IndexManager* IndexManager::instance_ = nullptr;
 
 void IndexManager::CreateInstance()
 {
@@ -39,7 +57,7 @@ void IndexManager::StartIndexingStream(StreamPtr stream)
   TaskManager::instance()->AddTask(index_task);
 }
 
-void IndexManager::StartConformingStream(AudioStreamPtr stream, const AudioRenderingParams &params)
+void IndexManager::StartConformingStream(AudioStreamPtr stream, AudioRenderingParams params)
 {
   if (IsConforming(stream, params)) {
     return;
@@ -97,3 +115,5 @@ void IndexManager::StreamConformAppendedEvent(const AudioRenderingParams &params
 {
   emit StreamConformAppended(static_cast<Stream*>(sender()), params);
 }
+
+OLIVE_NAMESPACE_EXIT