Log Message:
libansilove: update to 1.2.7.

libansilove 1.2.7 (2020-10-21)

- Error out early with ANSILOVE_FORMAT_ERROR in case ctx->length is 0
- Enable FORTIFY_SOURCE level 2
- Set CMAKE_BUILD_TYPE to "Release" in CMakeLists.txt
- Move variables declaration to the top of each loader function
- Initialize ansi_buffer and pcboard_buffer to NULL
- Refactor the IceDraw loader to use a state machine
- Check strndup() return value and error out on failed allocations
- Add some file format integrity checks in the IceDraw loader
- Add range integrity checks for scale_factor values in the output() function
- Return error code directly if ctx->length is 0 in the ANSI and PCBoard loaders
- Add range integrity checks for columns value in relevant loaders
- Add range integrity checks for bits value in relevant loaders
- Add additional file format integrity check in the XBin loader