merged the following changes from trunk into 1.8 branch:

PDFBOX-1622	r1512433
PDFBOX-1627	r1490022,r1490023
PDFBOX-1632	r1495799,r1497507
PDFBOX-1638	r1504214,r1515165,r1515905
PDFBOX-1639	r1493503
PDFBOX-1655	r1505737
PDFBOX-1657	r1504210
PDFBOX-1663	r1512661
PDFBOX-1681	r1512367
PDFBOX-1694	r1517273,r1517281
PDFBOX-1702	r1517288
PDFBOX-1735	r1528826
PDFBOX-1737	r1528833



git-svn-id: https://svn.apache.org/repos/asf/pdfbox/branches/1.8@1542735 13f79535-47bb-0310-9956-ffa450edef68