Created buttons in range form for infinity symbols.

Signed off by: Diego Araújo <diegoamc90@gmail.com>
Acceptance test for [-INF, INF] threshold
Merge pull request #100 from mezuro/range_inf_buttons

Range inf buttons
Fixed range numericality unit tests and added beginning greater than end validation.

Signed off by: Rafael Manzo <rr.manzo@gmail.com>
Added overlapping ranges validation.

Signed off by: Rafael Manzo <rr.manzo@gmail.com>
Fixed overlapping acceptance test for beginning uniqueness and range intersection
Range overlapping does not consider the reange itself for the edition case

Fixed infinity buttons acceptance tests that were trying to create overlapping ranges