Log Message:
Update to 1.6

Changelog:
1.6 (2011/11/07)
 * Remove matched information from context lines (Guillaume Nault)
 * Fix issue with single concurrency run (Eric Leblond)
 * Prepare 1.6 release. (Eric Leblond)
 * Fix context group separation (Guillaume Nault)
 * Fix docstring typo (Guillaume Nault)
 * Change field separator for context lines (Guillaume Nault)
 * Fix compatibility with python 2.5. (Eric Leblond)
 * Add a separator between blocks of matched lines (Guillaume Nault)
 * Avoid context line duplication (Guillaume Nault)
 * Add missing information in CocciMatch::display() docstring (Guillaume Nault)
 * Fix context line numbers (Guillaume Nault)