Merge pull request #17 from davidworkman9/master

check if tag has child nodes in pptx, xlsx, and docx before attempting t...
0.10.1
adding multiline test
fixes #16, moving to use j rather than binaries for spreadsheets, beefing up tests, adding rel notes
Add escape of the path for the tesseract command. Closes #18
Merge pull request #19 from voz/master

Add escape of the path for the tesseract command. Closes #18
0.11.1
updating to latest pdf-text-extract, fixes #20