check that insert query contain placeholder

[Lagovas]

after recent acra-rollback usage met case when it was helpful if acra-rollback check that query contains expected placeholder for example if user run from bash like:

acra-rollback arg1 arg1 --insert="some query $1" 

he will be surprised to see that output will not contain any decrypted data but select queries and decryption was executed. Because bash use $n as placeholders too :)

acra-rollback will take query with replaced value by bash (empty for example and placeholder will not placed in query)