Add vdebug:load_options() and vdebug:load_keymaps()

Provides option dictionary reloading after vdebug has been sourced.
Merge branch 'option-reload' into dev

Conflicts:
	plugin/vdebug.vim
DebuggerWatch: setlocal foldmethod=manual 

Lines with fold start marker are interpreted, if set fdm=marker.
Watch and Status window: configurable height

Example setting:
let g:vdebug_options["watch_window_height"]=45
let g:vdebug_options["status_window_height"]=5
Watch and Status window: default height
LogWindow: foldmethod=manual