Log Message:
Update to 0.1.7

Changelog:
libetonyek 0.1.7

- Fix a few issues found by Coverity.
- Correctly compute cell row and column.
- Improve reconstruction of gradients.
- Improve resolution of cell styles.
- Parse non-RGB colors.
- Improve handling of table border lines.
- Convert cell values to text in presentation and text documents.
- Handle following-paragraph and following-layout styles.
- Allow building with different versions of mdds (1.2 is the default).
- Require C++11 for build.
- Fix several issues found by oss-fuzz.
- Disable error output from libxml2.
- Improve lookup of parent styles.
- Never insert a page break in a footnote.
- Drop outdated MSVC project files.
- Various small fixes and improvements.