fix(uiSelectNoChoice): support bootstrap-multiple
fix(uiSelectNoChoice): support bootstrap-multiple

While using ui-select-no-choice directive it doesn't apply for multiselect 
mode (bootstrap theme). Appropriate markup was missed for multiselect 
mode in template for bootstrap theme.

Closes #1614 & #1615 
ConfidentCannabis/ui-select,granteagon/ui-select-temp,iOffice/ui-select,Crunch-io/ui-select,MartinDeHaan/ui-select-submitform,Jefiozie/ui-select,piebe/ui-select,angular-ui/ui-select,Vreasy/ui-select,Crunch-io/ui-select,prakashn27/ui-select,oncompass/ui-select,looker/ui-select,billypon/ui-select,MartinDeHaan/ui-select-submitform,piebe/ui-select,Crunch-io/ui-select,looker/ui-select,looker/ui-select,Servoy/ui-select,angular-ui/ui-select,ConfidentCannabis/ui-select,granteagon/ui-select-temp,Servoy/ui-select,prakashn27/ui-select,prakashn27/ui-select,WorktileTech/ui-select,Jobularity/ui-select,billypon/ui-select,ConfidentCannabis/ui-select,piebe/ui-select,billypon/ui-select,oncompass/ui-select,iOffice/ui-select,WorktileTech/ui-select,MartinDeHaan/ui-select-submitform,Jefiozie/ui-select,ivanvoznyakovsky/ui-select,Jefiozie/ui-select,Vreasy/ui-select,granteagon/ui-select-temp,Vreasy/ui-select,WorktileTech/ui-select,Jobularity/ui-select,oncompass/ui-select,Jobularity/ui-select,ivanvoznyakovsky/ui-select,Servoy/ui-select,ivanvoznyakovsky/ui-select,angular-ui/ui-select