Summary:
Add ValueParser file, base class, and subclasses for column types. Only NumericParser is used for now.
Add valueParser field to ViewFieldRec.
Use valueParser when parsing pasted text data in Grid and Detail views.
Test Plan: Add test to nbrowser CopyPaste suite, copying into a numeric column with different currency and locale settings.
Reviewers: dsagal
Reviewed By: dsagal
Differential Revision: https://phab.getgrist.com/D3082
