1. Each shape contains EscherContainerRecord(SpContainer). Shapes get and set all properties into EscherOptRecord.
2. HSSFShapeGroup takes coordinates from EscherSpgrRecord.
3. Added tests for creating new HSSFSimpleShape from scratch and reading from existing file
4. Improved work with anchors.
git-svn-id: https://svn.apache.org/repos/asf/poi/branches/gsoc2012@1351484 13f79535-47bb-0310-9956-ffa450edef68