Don't show amount range if there is no amount range

[ripcurlx]

In some screens (e.g. take offer, my open offers,...) we display the amount range, even if there is no amount range. In the cases like my open offers it should be displayed e.g 0.10 instead of 0.10-0.10 or in cases like the take offer screen hide this field at all.

Take Offer

My Open Offers

[tr37ion]

Splitting those two values in two columns make them better readable and sortable in the list.