Embedding/IPCLiteAPI

Lite-weight Embedding IPC API for Mozilla based applications with native UI.

Basic architecture is very close to WebKit2, and MicroB

Benefits of new architecture comparing to default mozilla embedding

* No XUL/XPCOM heavy content in UI process (Best memory footprint, fast startup)
* IPC use current Mozilla Chromium/IPDL implementation (mostly tested with current FF/Mobile)
* Rendering based on Shadow/Shadowable layers tree (same as content rendering in XUL Mobile FF)
* IPC provide ability to load memory greedy content in child process and kill it without increasing memory usage for Main UI application process