some refactoring

* massive changes inside includes, drop unused definitions
* rewrite some initialization methods to avoid additional
freeing/allocation
* drop some explicit destructors calls

sources/extsysmonsources/upgradesource.cpp

@@ -37,8 +37,6 @@ UpgradeSource::UpgradeSource(QObject *_parent, const QStringList &_args)
 UpgradeSource::~UpgradeSource()
 {
     qCDebug(LOG_ESS) << __PRETTY_FUNCTION__;
-
-    delete m_extUpgrade;
 }