bare-metal: Add support for KEIL toolchain

This patch adds support for the toolchains, provided by
KEIL:

 * http://www.keil.com/c51/
 * http://www2.keil.com/mdk5/

Now QtC's compiler page have additional 'KEIL' selector
which allows to user to choose a desired C/C++ compiler
from set of the KEIL toolchains.

In this case the QtC will tries to detect the compiler ABI,
in which was added the additional OMF binary format type
which is produced by C51 compiler:

 * http://www.keil.com/support/docs/93.htm

Currently are supported the following architectures:

 * ARM
 * 8051 (aka MCS51)

In addition, were added changes to the QBS Project Manager
plugin to make it work with QBS 1.13 (where previously were
added support for KEIL toolchain).

So, now do not need to do an additional 'hacks' into the
'qbs.toolchain' property of QtC KEIL kit.

Following features are not implemented yet:

* Debugger integration.
* Compile output parsers.
* Toolchains auto-detection.
* Support for C251, C166 architectures.

Change-Id: If0cc18d22b7dc0e5ce9096bdb3dc699ee3edde66
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/qbsprojectmanager/defaultpropertyprovider.cpp

@@ -133,6 +133,8 @@ static QStringList toolchainList(const ProjectExplorer::ToolChain *tc)
         list << QLatin1String("msvc");
     else if (tc->typeId() == BareMetal::Constants::IAREW_TOOLCHAIN_TYPEID)
         list << QLatin1String("iar");
+    else if (tc->typeId() == BareMetal::Constants::KEIL_TOOLCHAIN_TYPEID)
+        list << QLatin1String("keil");
     return list;
 }