New parameter .id for ldply() to specify name of index column (default: .id); fixes # 140; fixes # 107
New parameter .id for rdply() to specify name of index column (default: .n); fixes # 142
update Rd files
Generate .id column as factor in ldply(); fixes # 137
add NEWS
Merge pull request #187 from krlmlr/mute-l_ply-note

Mute note about "no visible binding for d" by creating an unused variable with this name
Merge pull request #188 from krlmlr/fix/140-142-id-137-column-as-factor

Enhancements for *dply
fixes # 158 by evaluating the .expr parameter and calling it one time less if it actually is an expression and not a function
update NEWS