Python-yara

BUGFIX: Accept the "+" character as valid in DLL names (1501).
BUGFIX: Buffer overrun in "macho" module.
BUGFIX: Undefined behavior in Windows implementation of yr_filemap_xxx functions (1302).
BUGFIX: Crash due to consecutive jumps in hex strings (1492).

* Don't raise warnings for non-ASCII strings.

* New operators `icontains`, `endswith`, `iendswith`, `startswith`, `istartswith`.
* Raise warnings for non-ascii strings.
* Accept `\t` escape sequence in text strings.
* Add `--no-follow-links` command-line option to `yara`.
* Prevent `yara` from following links to "." (1d2d).
* Implemented [non-blocking scanning API]([https://github.com/VirusTotal/yara/commit/cba6932759ec16a61288b1314b3aee1103ad03ec](https://github.com/VirusTotal/yara/commit/cba6932759ec16a61288b1314b3aee1103ad03ec)) (simonhf).
* When a string causes too many matches, YARA raises a warning instead of failing.