so they match the Q* counterparts more closely:

ProString: startsWith(), endsWith(), indexOf(), lastIndexOf(),
contains(), at(), length(), QTextStream::operator<<(), toLatin1(),
toInt() & toShort()

ProStringList: length(), removeAt(), contains()

Change-Id: Iab78236f7152f6a4b93709abbf59b9027c44ba2c
Reviewed-by: Daniel Teske <daniel.teske@nokia.com>