[ci] [vst] Shorten compilation time to avoid Travis timeouts.
[ci] [vst] Shorten compilation time to avoid Travis timeouts.

We remove the progs target [examples] to save time, we still build the
full library thou.

I guess we can't do better for now unless we get some Travis
subscription.

maximedenes/coq,coq/coq,JasonGross/coq,ejgallego/coq,coq/coq,JasonGross/coq,gares/coq,maximedenes/coq,JasonGross/coq,Matafou/coq,ppedrot/coq,ejgallego/coq,SkySkimmer/coq,letouzey/coq-wip,gares/coq,Zimmi48/coq,letouzey/coq-wip,Zimmi48/coq,ejgallego/coq,SkySkimmer/coq,JasonGross/coq,silene/coq,ppedrot/coq,gares/coq,gares/coq,ppedrot/coq,Matafou/coq,letouzey/coq-wip,ejgallego/coq,letouzey/coq-wip,ppedrot/coq,coq/coq,maximedenes/coq,Zimmi48/coq,gares/coq,Matafou/coq,ppedrot/coq,letouzey/coq-wip,SkySkimmer/coq,silene/coq,maximedenes/coq,SkySkimmer/coq,coq/coq,Zimmi48/coq,silene/coq,maximedenes/coq