Version Update for 1.5.1

Toolbar icon fix for Windows (system tray)

Fix warnings in Mac build

Minor but annoying warnings from the mac build fixed.
 * Incorrect duplication of header causing moc build rule duplication
in generated makefile
 * you aren’t supposed to use char as an array type, probably because
it can be a signed type in some compilers. Negative array indexes are
problematic.

Version bump for windows fix

Merge pull request dogecoin#97 from billym2k/master

checkpoints for fork

Merge pull request dogecoin#52 from billym2k/master

Fix dust issue

Merge pull request dogecoin#52 from billym2k/master

Fix dust issue

Merge pull request dogecoin#32 from jaekwon/master

Fixed segmentation error