Doc: move Class View plugin docs to .cpp files.

QDoc does not find docs in the .h files.
Use \brief only for namespaces, classes, enums, and properties.
Use standard wording for \brief and \fn.
Use \a and \c according to guidelines.

Fix grammar and style.

Change-Id: Ib685a03c97ef38661ecc156f61d70085514357fc
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>

src/plugins/classview/classviewsymbollocation.cpp

@@ -34,6 +34,14 @@
 namespace ClassView {
 namespace Internal {
 
+/*!
+    \class SymbolLocation
+    \brief The SymbolLocation class stores information about symbol location
+    to know the exact location to open when the user clicks on a tree item.
+
+    This class might be used in QSet and QHash.
+*/
+
 SymbolLocation::SymbolLocation() :
     m_line(0),
     m_column(0),