moved (variant)has_substitute and (variant)find_substitute into traits
Fix for case where a single-element sequence is not being moved into a variant that can accept it.
cleanup
added mising files
various sequence handling fixes
Subcontext fixes and formatting
Added type-erased parser, tests and examples
Moved is_parser trait to its own file
new facade-based API
Merge pull request #13 from jamboree/develop

x3 new facade-based API
fix transform_params/ fix integer_sequence for clang
Merge pull request #15 from jamboree/develop

fix transform_params/ fix integer_sequence for clang
Quality get with x3::get
Qualify get with x3::get
Qualify get with x3::get
Fixed const issue in attr_parser
Fixes for boost::optional explicit operator bool
Merge pull request #17 from wichtounet/patch-1

Qualify get with x3::get