Merge pull request #1 from adlnet/master

get commits from adl master
4.1 optional/recommended/mandatory
Section 6.0-6.3 Edits

Moved some text around, please note requirements
separation/recategorization.  Changed Runtime to Run-time.
Section6.4 Edits

Moved some sections and changed some headings.  Added a link where
appropriate.
PR Regarding Failed Statements and Batches

For Issue #70
IRL Definition

We never really got a chance to clarify usage in the document.  Rather
than root it out at each place, let's just define IRL.  If it doesn't
stick for the next version, we can figure out what rules we really mean
surrounding it then.
Version not recommended
Removed first requirement, moved other requirement
Merge pull request #400 from andyjohnson/failedstatementedits

PR Regarding Failed Statements and Batches
Updated Activity Definition

To work around PR #399
Comma
Merge pull request #407 from andyjohnson/ActivityDef2

Activity def2
Merge pull request #2 from adlnet/master

get commits from adl master
Changed Sub-Statement to SubStatement when reffering to objectType
Merge pull request #410 from garemoko/substatement

Use Substatement instead of Sub-statement for objecttype
Ben comment updates

Updated 1.0.0 to 1.0.1 in correct places. I removed the Header
Requirement as it was confusing, kept the LRS requirement and added new
Client requirements.  The language was modified slightly and moved into
details.
Fixed conflict, changed above to below
Update xAPI.md

Missing hash mark on Language Map link in Object section (4.1.4.1).
Added Appendix H: Table of Endpoints

Endpoint Table and updated TOC
Merge pull request #411 from zachlowry/patch-1

Update xAPI.md