Fix handling of CommandInterpreter's events in lldb-mi

Fix handling of CommandInterpreter's events in lldb-mi

Summary:
Previously lldb-mi contains a stub for that but it didn't work and all CommanInterpreter's events were ignored.
This commit adds a handling of CommandInterpreter's events in lldb-mi.

Steps:
# Fix CMICmnLLDBDebugger::InitSBListener
# Add SBCommandInterpreter::EventIsCommandInterpreterEvent
# Exit on lldb::SBCommandInterpreter::eBroadcastBitQuitCommandReceived

All tests pass on OS X.

In further we can remove "quit" hack in lldb-mi.

Test Plan:
# Create start_script file:
```
target create ~/p/hello
b main
r
quit
```

# Run lldb-mi --interpreter
# Execute start_script file by following command:
```
-interpreter-exec console "command source start_script"
```

Log:
```
$ bin/lldb-mi --interpreter
(gdb)
-interpreter-exec console "command source start_script"
Executing commands in '/Users/IliaK/p/llvm/build_ninja/start_script'.
(lldb) target create ~/p/hello
Current executable set to '~/p/hello' (x86_64).
(lldb) b main
Breakpoint 1: where = hello`main + 29 at hello.cpp:12, address = 0x0000000100000e2d
(lldb) r
Process 1582 launched: '/Users/IliaK/p/hello' (x86_64)
(lldb) quit
^done
(gdb)
=thread-created,id="1",group-id="i1"
=thread-selected,id="1"
(gdb)
=shlibs-added,shlib-info=[num="1",name="hello",dyld-addr="-",reason="dyld",path="/Users/IliaK/p/hello",loaded_addr="-",dsym-objpath="/Users/IliaK/p/hello.dSYM/Contents/Resources/DWARF/hello"]
...
=shlibs-added,shlib-info=[num="132",name="libDiagnosticMessagesClient.dylib",dyld-addr="0x7fff91705000",reason="dyld",path="/usr/lib/libDiagnosticMessagesClient.dylib",loaded_addr="0x7fff91705000"]
(gdb)
*stopped,reason="breakpoint-hit",disp="del",bkptno="1",frame={addr="0x100000e2d",func="main",args=[{name="argc",value="1"},{name="argv",value="0x00007fff5fbffc88"}],file="hello.cpp",fullname="/Users/IliaK/p/hello.cpp",line="12"},thread-id="1",stopped-threads="all"
(gdb)<press Enter>

MI: Program exited OK
```

Reviewers: abidh, clayborg

Reviewed By: abidh

Subscribers: jingham, lldb-commits, clayborg, abidh

Differential Revision: http://reviews.llvm.org/D8382

llvm-svn: 232891