Fix input form according to @yannick's pull #126

Agreeable changes were pulled in from pull request #126 by @yannick at
yw/sequenceserver.

Signed-off-by: Vivek Rai <vivekraiiitkgp@gmail.com>
`btn-info` keeps the color light and hover effects are more noticeable. This color goes in line with the dropdown style chosen in other pull.