Merge pull request #1 from cmorse/master

Added a .gitignore for files auto-generated by the CMake build-system
Some files didn't get bumped to 4.06
Added changes from upstream version 4.06. Bumped to version 4.07

Upstream changelog: Version 4.06, 14 May 2013
Added support for Javascript type comments, i.e. // and /* */
Added json_spirit_writer_options.h to CMake install
Improved error message on attempt to extract the wrong type of data from
a value
Correct bug that reduced write performance
Added always_escape_nonascii writer flag