Partial rewrite of 4.1.4 Object

subsection 4.1.4.1 to follow. Was not changed because too complex. Need
some co-writing done on my own fork before commit can be made.

Notable differences in this one: switched the order of StatementRef and
Sub-Statements. Made more sense while writing the 'Rationale' and I
expect StatementRef to be used more frequently.
Merge pull request #24 from paul-esch/master

get paul master (right branch this time!)
Standardized headings in 4.1

For the third time....
Clarified examples
re-added link to verbs section

I guess this was removed accidentally
amended 4.1.4.3 rationale
commit just in case

Not sure if I changed anything with this commit!
Conversion fixes

Addressed some invalid 0.9 statements
Added conversion for non-URI extension keys
Merge branch 'master' of https://github.com/adlnet/xAPI-Spec
Fixed typo
Merge pull request #2 from garemoko/PaulObject

garemoko's suggested changes.
typos

minuscule typo and added code block quotes becaus Github wouldnt render.
Merge branch 'master' of https://github.com/adlnet/xAPI-Spec
Merge branch 'master' of https://github.com/adlnet/xAPI-Spec
clarify statement ref behavior. Closes #152
line length
Merge pull request #139 from bscSCORM/conversion

Conversion fixes -- ALSO REVIEW: all of Appendix E
Clean up 'HTTP Basic Authentication' statement usage
Missing target anchor in par. 6.4.1
Added signed statements section & example