Initial checkin of curses-based LLDB UI (lui)

LLDB (Terminal) User Interface
==============================
This directory contains the curses user interface for LLDB. To use it, ensure Python can find your lldb module. You may have to modify PYTHONPATH for that purpose:

$ export PYTHONPATH=/path/to/lldb/module

Then, run the lui.py. To load a core file:
$ ./lui.py --core core

To create a target from an executable:
$ ./lui.py /bin/echo "hello world"

To attach to a running process:
$ ./lui.py --attach <pid>


Known Issues
============
1. Resizing the terminal will most likely cause lui to crash.
2. Missing paging in command-window
3. Only minimal testing (on Ubuntu Linux x86_64)

Missing Features
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- stdin/stdout/stderr windows
- memory window
- backtrace window
- threads window
- tab-completion
- syntax-highlighting (via pygments library)
- (local) variables window
- registers window
- disassembly window
- custom layout