Fix bug requiring software restart to display new stake.
Change "Bitcoin" to "Peercoin"

A couple where Bitcoin was still used in the GUI switched to Peercoin.
Merge pull request #44 from glv2/qt-stake

Fix bug requiring software restart to display new stake
pb invoice 20140515
Update pbinvoice20140501.txt
Merge pull request #52 from pennybreak/master

pb invoice 20140515