Add support for edit_file and edit_file_lines (ef/efl) from File::Slurp

[ironcamel]

From Uri Guttman:

hi,

someone pointed me to App:p as it uses File::Slurp. you should look at the latest version from last year which has edit_file and edit_file_lines in it. those would be even more useful than read_file/write_file. i plan to optionally export them as ef and efl too.

if you didn't know, i am the author of File::Slurp. :)

thanx,

uri

[kyzn]

It seems App-p is using File::Slurper now, and there's no edit_file and edit_file_lines in that one.