Add str.captialize

[Uwe L. Korn]

• ✔️ pandas function
• ✔️ Python function
• ❌ C++ STL function
• ✔️ no need for a regular expression library
• ❌ need for a Unicode database for capitalization
• ❌ cannot pre-compute output size as capital letters could have a different byte-width

Pseudo-Code:

Inputs: -

builder = StringBuilder()
for row in rows:
    builder.append(map_utf8_chararcters(utf8_captitalize, row))