Hyu/nfr customize local vars

[huawenyu]

@geneotech If you have time, please help me review & modify this new features:

• Support menu when add breakpoint, startup, etc.
• Using MVC to support view-var (Alt+v), view-break(Alt+b), view-frame(Alt+f)
• View-var support customize var type define as:

" neogdb.vim: Get more detail variable data
let g:neogdb_vars = {
      \ 'struct my_str *' : ['{}->val', '{}->len'],
      \ }

[geneotech]

@huawenyu I'm quite preoccupied at the moment with working on editor for my game, but it is possible that I'll need some means of debugging once I'm done with the implementation - I'll probably look into this then.

In the meantime, could you please update README.md so that it only contains up-to-date instructions? It appears that there are some old commands mentioned, e.g. the old :GdbLocal instead of :Nbgdb.

It'd also be nice if you documented how the user is supposed to properly configure NeoGDB, e.g. how to specify the executable path and command arguments, initial window options etc. - that is sure to draw in more users, and will make my testing a whole lot easier!

[huawenyu]

Thanks for your reply. The branch ideal of git is very good, so I can stay on the feature branch and not bother others, and also give us enough time to improve it. You can review the code when you have free time. I'll update the readme, keep continue polish the feature when I using it.