Retire the Text_Matcher and Regex_Matcher and update the column selectors.

[wdanilo]

This task is automatically imported from the old Task Issue Board and it was originally created by James Dunkerley.
Original issue is here.

---

type Column_Selector
    ## Selects columns based on their names.

      - names: Set of names to match.
      - case_sensitivity: Specifies whether the matching should be case sensitive.
      - use_regex: Allow regular expression based patterns.
    By_Name (names : Vector Text) (case_sensitivity:Case_Sensitivity=Case_Sensitivity.Sensitive) use_regex=Boolean=False

    ## Selects columns by their index.

       - indexes: Set of indexes to match.
         The index of the first column in the table is 0. 
         If the provided index is negative, it counts from the end of the table
         (e.g. -1 refers to the last column in the table).
    By_Index (indexes : Vector Integer)

This also removes support for selecting by column. This only worked by matching on name in a case sensitive way (not on the specific column instance). The other uses become:

type Column_Name_Mapping
    ## Selects columns based on their names.

      - names: Map of old names to find with replacements.
        If use regular expression, the special replace patterns can be used.
      - case_sensitivity: Specifies whether the matching should be case sensitive.
      - use_regex: Allow regular expression based patterns.
    By_Name (names : Map Text Text) (case_sensitivity:Case_Sensitivity=Case_Sensitivity.Sensitive) use_regex:Boolean=False

    ## Selects columns by their index.       

      - indexes: Map of indexes with the new name.
        The index of the first column in the table is 0. If the provided index is
        negative, it counts from the end of the table (e.g. -1 refers to the last
        column in the table).
    By_Index (indexes : Map Integer Text)

    ## Selects columns by position starting at the first column until the
       new_names is exhausted.
    By_Position (new_names : [Text])

[jdunkerley]

Covered Column_Selector by #5646, still to work on Column_Name_Mapping.

[enso-bot]

James Dunkerley reports a new STANDUP for today (2023-02-20):

Progress: Fixed the viz for 2D vectors. Removed the Column_Name_Mapping type and am restructuring the rename_columns. It should be finished by 2023-02-21.

Next Day: Finish rename columns, backlog tidy and iteration assignments. Hopefully DB/InMemory alignment checks

[enso-bot]

James Dunkerley reports a new STANDUP for today (2023-02-21):

Progress: Finished the rename_columns work. Added first_row, second_row and last_row to the Table. Sorted the backlog into milestones and tidied up a lot. It should be finished by 2023-02-21.

Next Day: Next day I will be working on the #5713 task. Design for the MVP for writing data to files and the database.