As discussed with Joel de Guzman this PR introduces the expect directive
expect[] to spirit qi 2. PR includes code, test, example, and
documentation.
See
https://sourceforge.net/p/spirit/mailman/spirit-general/thread/nln5d3%24klg%241%40ger.gmane.org/#msg35208052
Here is what I did:
1. Added expect.hpp to home/qi/directives.
1a. Added forwarding header qi_expectd.hpp to include dir.
2. Renamed expectation parser (a > b) struct from expect to
expect_operator
to prevent name conflicts (expect directive uses struct
expect_directive).
3. Added expect directive to the common terminals
(common_terminals.hpp).
4. Added expectd.cpp to the test suite.
5. Added expectd.cpp to the examples.
6. Added expect directive documentation to directive.qbk. Crosslinked
expectation operator and expect directive docs.
7. Added expect directive to the index.idx file for index-generation.
8. Added expect directive to the qi quick_reference.qbk.
9. Added expect directive to the spirit reference card (tex, pdf)
10. Created a new section in the whats_new.hpp.
11. Changed spirit version to 2.5.4. Spirit index.html showed 2.5.2
allthough an 2.5.3 What's New section already existed. Fixed.
