feat: add omit and pick

[leognutzmann]

• Pick function:
  Adds Pick function, which generates a new map containing the specified keys. Any keys that do not exist in the original map are ignored.
• Omit Function:
  Adds Omit function, designed to produce a new map that excludes the specified keys. Similar to Pick, any non-existent keys in the original map are ignored.

[elliotchance]

I'm fine with the content, but I'm not convinced on the naming of the functions. Is there an existing language or library that uses this terminology?

[leognutzmann]

Yes, there is:
https://ramdajs.com/docs/#omit
https://ramdajs.com/docs/#pick