Fix manpage formatting
Show INFINITY score in location constraints
Show INFINITY score in colocation constraints
Show INFINITY score in order constraints
Provide better error message when moving/banning stopped resource
Check for invalid score in 'pcs constraint location'

* move score validation to function and make it not raising
  IndexError on empty string
* validate the score before puting it into the CIB
* validate the score before changing its sign
  * avoid raising IndexError
  * avoid confusing user by score with opposite sign in error message
    when using 'pcs constraint location <resource> avoids' command