Fix critical spelling errors
Fix vnames construction with YEAR_WITHIN.  Must be head(...) here!

Damian changed earlier for some reason…
Suppress warnings in test.projection.iter from comparison of objects of unequal length with ==
Add omitted return.projection.group.identifier arg
Add as.character for cases when @SGP$SGPercentiles is NULL
Allow for multiple sgp.projection.sequence in sgp.config

For SCIENCE in GA analyses.  This expands a single sgp.iter into two or
more projection sequences.
Fix accented o - convert to ascii code
Merge branch 'master' of github.com:CenterForAssessment/SGP
Merge pull request #633 from adamvi/master

Multiple projection sequences and other misc.
Merge branch 'master' of https://github.com/CenterForAssessment/SGP