[cleanup] cleanup scripts/lonelypages.py
[cleanup] cleanup scripts/lonelypages.py

- use single quotes for string literals and double quotes
  **only** if they consist of single quotes within them
- use str.format(...) instead of modulo for type specifier
  arguments
- remove preleading "u" from strings

Change-Id: I2cbc7438b4bf3fb2d7642ef7df41a9c9ff1e7156

wikimedia/pywikibot-core,wikimedia/pywikibot-core,PersianWikipedia/pywikibot-core