Misc

[matthieugomez]

• I changed the syntax of setcolorder. This solves setcolorder could accept a vector of column names of length lower than the number of columns #798 and [R-Forge #2490] Add new movecol(DT, "colname", 1) function #592 in a way consistent with how setnames works. When only one argument is given (beyond the data.table) , setcolorder behavior does the exact same thing as before. However, I renamed this argument from "neworder" to "old" to be consistent with setnames. A second argument (a numeric vector) can now be specified. Tests added
• rename by argument of na.omit by cols.
• regex and wildcard can be used in .SDcols. This solves Wildcards #817
• Enclosing by argument of [.data.table by "()" makes sure NSE is not used, similarly to LHS in :=
• New classes IMonth and IQuarter. Elapsed month and quarters are useful in a lot of cases. An example is to use the roll option with respect to 1 month since one cannot use roll = month(1). yearmon and yearqtr exist in zoo but they are stored as double (elapsed year + 1/12 or 1/4). I wrote these integer classes for personal use. Discovering IDate and ITime, it makes sense to add them here.

Sorry I though squashing commits meant merging PR.

[arunsrinivasan]

Too many things here. Would be nice to have as separate PRs, and would be nice to discuss first (so as to avoid wasting your time).