Started new lesson on flow control with R that doesn't include image manipulation.
Added motivating section on saving plots.
Added section on conditional statements.
Added some extra explanation on boolean variables and logical tests.
Added challenge for conditional statements section.
Added section on automatically generating figures.
Added objectives and key points.
Added next steps.
Added print done to novice R lesson 04 in order to be consistent with diagram.
Incorporate wording suggestions from review by @jhollist on novice R lesson 04-cond.
Clarify that body of conditional statement is defined by curly braces and not indentation.
Add note on closing out multiple calls to pdf and checking plotting status with dev.cur.
Merge pull request #718 from jdblischak/04-cond

"Translation" of novice Python lesson on flow control to R