Add -exec-arguments command

Summary:
This patch adds -exec-arguments command for lldb-mi. -exec-arguments command allows to specify arguments for executable file in MI mode. Also it contains tests for that command.

Btw, new added files was formatted by clang-format.

Reviewers: abidh, zturner, clayborg

Reviewed By: clayborg

Subscribers: zturner, emaste, clayborg, jingham, lldb-commits

Differential Revision: http://reviews.llvm.org/D6965

llvm-svn: 229110
diff --git a/lldb/source/API/SBLaunchInfo.cpp b/lldb/source/API/SBLaunchInfo.cpp
index 007451e..681f5fe 100644
--- a/lldb/source/API/SBLaunchInfo.cpp
+++ b/lldb/source/API/SBLaunchInfo.cpp
@@ -36,6 +36,12 @@
     return *m_opaque_sp;
 }
 
+const lldb_private::ProcessLaunchInfo &
+SBLaunchInfo::ref () const
+{
+    return *m_opaque_sp;
+}
+
 lldb::pid_t
 SBLaunchInfo::GetProcessID()
 {