Not good idea
  Implement this option `pads`. This option is equivalent to the one in
    `THStack`. It allows to draw all the `TGraphs` in separated pads.
Merge branch 'master' of https://root.cern.ch/git/root
ROOT-5937: support ioname and iotype in selection xmls

The idea is to hardwire the iotype/ioname into the system.
This happens in 2 steps:
1) In the dictionaries, in code as we do for the "comment" field,
we can add attributes to the members for which an iotype/name is
specified in the selection xml. This will allow us to carry this
information around
2) In the TCling methods:
 - const char* TCling::DataMemberInfo_TypeTrueName(DataMemberInfo_t* dminfo) const
 - const char* TCling::DataMemberInfo_Name(DataMemberInfo_t* dminfo) const
 - const char* TCling::DataMemberInfo_TypeName(DataMemberInfo_t* dminfo) const
we can check which attributes we have and return the iotype/name if
we need.

The implementation is nothing to be proud about as it uses an internal cache.
It is not possible to use the buffer where the actual attribute is because
it may not be null terminated. So using llvm::stringRef::data() is not an option.
A review of the interfaces is of course possible as they are for internal use
only.
Invalid font index in case of italic 'symbol' font.
Correct typos in error messages.
Fix ROOT-6113: include in ioreadrules properly considered
Small performance optimisation
Delay graphics initialization

Delay initialization of graphics subsystem by moving gApplication->InitializeGraphics from static initialisation (when loading library) to a static method called when instanciating gClient. This fixes the Jira issue #ROOT-6106
The underlying issue is a recursive call to JIT, for example when the loading a library is triggered by a symbol resolution lookup, and the static initialization of the library itself try to use the interpreter (e.g. via the plugin manager)
root.exe: interpreter/llvm/src/lib/ExecutionEngine/JIT/JIT.cpp:467: void llvm::JIT::runJITOnFunctionUnlocked(llvm::Function*, const llvm::MutexGuard&): Assertion `!isAlreadyCodeGenerating && "Error: Recursive compilation detected!"' failed.
Revert "ROOT-5937: support ioname and iotype in selection xmls"

roottest has shown that the changes cause instabilities on some platforms.
They are rolled back here in order for me to further investigate the problem.

This reverts commit c03e8fbfa916a96e055ba9e01c981156a5155bf1.
Port the changes done on 5.34 patches branch. Fix stressProof test.
Fix memory leak (ROOT-6116).
Add and use TClass::IsVersioned

'Foreign' has been meaning (for a while) only that the class does
not have a Streamer function and thus does not have a ClassDef.

This does not mean (and hasn't for a while) that the class layout
is not versioned as the version can be set externally via either
the linkdef or the selection or the RootClassVersion macro.

So add TClass::IsVersioned to clarify.

This fixes ROOT-6114
Use markdown
Fix a wrong init.
Remove redundant fwd decl.
Bind cxa_atexit to the Transaction instead of the Decl.
No llvm.global_dtors variable in the module.
This should be reimplemented. So far it is a nop.
Doesn't depend on neither the module nor the execution engine.