Properly disable sound on errors on MacVim
Properly disable sound on errors on MacVim

Current configuration was not disabling that annoying sounds on MacVim. According to help:

```
Use visual bell instead of beeping.  The terminal code to display the
	visual bell is given with 't_vb'.  When no beep or flash is wanted,
	use ":set vb t_vb=".
	Note: When the GUI starts, 't_vb' is reset to its default value.  You
	might want to set it again in your |gvimrc|.
```
alexnguyen91/vimrc,nahwar/my-vim-config,jcestlavie/vimrc,nahwar/my-vim-config,lavender-flowerdew/vimrc,UX-Anakin/VIMRC,jimjing/vimrc,ChrisOHu/vimrc-1,spino327/vimrcsp,anymuse/vimrc,sonictk/vimrc,killuazhu/vimrc,ballercat/vim-settings,stevenswong/vimrc,ChrisOHu/vimrc,DocHoncho/vimrc,freohr/vimrc,killuazhu/vimrc,alexjab/vimrc,liangxiaoju/vimrc,killuazhu/vimrc,wming126/vimrc_github,spino327/vimrcsp,spino327/vimrcsp,alexnguyen91/vimrc,nahwar/my-vim-config,ballercat/vim-settings,spino327/vimrcsp,jimjing/vimrc,alexnguyen91/vimrc,jcestlavie/vimrc,derwentx/vimrc,jladuval/vimrc,markguo/myvimconf,tkshredz23/vimrc,wming126/vimrc_github,jcftang/vimrc,markguo/myvimconf,NcLang/vimrc,qhadron/vim_config,derwentx/vimrc,ekcode/vimrc,anymuse/vimrc,tkshredz23/vimrc,hyliker/vimrc,DocHoncho/vimrc,lavender-flowerdew/vimrc,jcftang/vimrc,lavender-flowerdew/vimrc,timothyjamesjensen/vimrc,IanZhao/.vim,NcLang/vimrc,qhadron/vim_config,reAsOn2010/vimrc,alexjab/vimrc,dpendolino/vimrc,amix/vimrc,timothyjamesjensen/vimrc,liangxiaoju/vimrc,khatchad/vimrc,freohr/vimrc,off99555/vimrc,trevorijones/vimrc,hyliker/vimrc,off99555/vimrc,ekcode/vimrc,khatchad/vimrc,nahwar/my-vim-config,mishadev/vimrc,ChrisOHu/vimrc,stevenswong/vimrc,phylroy/vimrc,timothyjamesjensen/vimrc,khatchad/vimrc,iwifigame/vimrc,UX-Anakin/VIMRC,jimjing/vimrc,khatchad/vimrc,nahwar/my-vim-config,jimjing/vimrc,jcestlavie/vimrc,markguo/myvimconf,sonictk/vimrc,UX-Anakin/VIMRC,qhadron/vim_config,khatchad/vimrc,qhadron/vim_config,anymuse/vimrc,stevenswong/vimrc,jcftang/vimrc,dpendolino/vimrc,ChrisOHu/vimrc,qhadron/vim_config,mishadev/vimrc,killuazhu/vimrc,xelliott/vimrc,lavender-flowerdew/vimrc,xelliott/vimrc,xelliott/vimrc,phylroy/vimrc,liangxiaoju/vimrc,timothyjamesjensen/vimrc,UX-Anakin/VIMRC,tkshredz23/vimrc,liangxiaoju/vimrc,ChrisOHu/vimrc-1,hyliker/vimrc,derwentx/vimrc,jimjing/vimrc,xuev/vimrc,markguo/myvimconf,iwifigame/vimrc,phylroy/vimrc,jladuval/vimrc,sonictk/vimrc,timothyjamesjensen/vimrc,NcLang/vimrc,ChrisOHu/vimrc,alexjab/vimrc,phylroy/vimrc,spino327/vimrcsp,markguo/myvimconf,davespanton/vimrc,tkshredz23/vimrc,wming126/vimrc_github,khatchad/vimrc,sabaka/vimrc,khatchad/vimrc,jcestlavie/vimrc,hyliker/vimrc,khatchad/vimrc,hyliker/vimrc,ivan19871002/vimrc,UX-Anakin/VIMRC,trevorijones/vimrc,sonictk/vimrc,xuev/vimrc,stevenswong/vimrc,NcLang/vimrc,davespanton/vimrc,ballercat/vim-settings,off99555/vimrc,dpendolino/vimrc,sonictk/vimrc,khatchad/vimrc,ekcode/vimrc,ivan19871002/vimrc,ChrisOHu/vimrc-1,reAsOn2010/vimrc,davespanton/vimrc,xelliott/vimrc,khatchad/vimrc,lavender-flowerdew/vimrc,xuev/vimrc,off99555/vimrc,mishadev/vimrc,wming126/vimrc_github,killuazhu/vimrc,dpendolino/vimrc,ChrisOHu/vimrc,stevenswong/vimrc,khatchad/vimrc,anymuse/vimrc,alexjab/vimrc,xelliott/vimrc,amix/vimrc,nahwar/my-vim-config,amix/vimrc,anymuse/vimrc,orland0m/vimrc,stevenswong/vimrc,xuev/vimrc,lavender-flowerdew/vimrc,phylroy/vimrc,killuazhu/vimrc,davespanton/vimrc,khatchad/vimrc,ivan19871002/vimrc,ChrisOHu/vimrc-1,xuev/vimrc,UX-Anakin/VIMRC,off99555/vimrc,dpendolino/vimrc,markguo/myvimconf,sonictk/vimrc,jcestlavie/vimrc,ekcode/vimrc,NcLang/vimrc,tkshredz23/vimrc,jcftang/vimrc,amix/vimrc,dpendolino/vimrc,ChrisOHu/vimrc-1,reAsOn2010/vimrc,jladuval/vimrc,DocHoncho/vimrc,reAsOn2010/vimrc,anymuse/vimrc,wming126/vimrc_github,NcLang/vimrc,alexjab/vimrc,mishadev/vimrc,phylroy/vimrc,jcestlavie/vimrc,khatchad/vimrc,ballercat/vim-settings,reAsOn2010/vimrc,ivan19871002/vimrc,IanZhao/.vim,NcLang/vimrc,spino327/vimrcsp,DocHoncho/vimrc,timothyjamesjensen/vimrc,alexnguyen91/vimrc,hyliker/vimrc,mishadev/vimrc,alexjab/vimrc,davespanton/vimrc,DocHoncho/vimrc,ChrisOHu/vimrc,phylroy/vimrc,khatchad/vimrc,wming126/vimrc_github,mishadev/vimrc,wming126/vimrc_github,ChrisOHu/vimrc-1,khatchad/vimrc,ballercat/vim-settings,ChrisOHu/vimrc,jcftang/vimrc