add advanced exclusion mechanism

[Gaëtan Lehmann]

exclusion mechanism is currently too limited: * it is not possible to exclude a directory * it is not possible to exclude a single line it should be enhanced to support these two use cases

[Evgeny Smirnov]

Agree

[Gaëtan Lehmann]

enhanced exclusion mechanism - see #23

the exclusion files are now parsed as a set of regular expressions that match the log output in the standard format with the rule name. If the regular expression match, the report is excluded. For example, to exclude all the T003 report for the 'case' and 'delete' keyword, just add this line to ane exclusion file

:\d+: T003: keyword '(case|delete)' not followed by a single space

the empty lines are ignored in the exclusion files as well as the lines beginning with a #, so the file can be commented and formatted a bit

→ <<cset 398bc4921b2c>>

[Gaëtan Lehmann]

still have to write some doc. old tcl exclusion files are still supported but should be deprecated

[Gaëtan Lehmann]

doc added in 2e5810

[Gaëtan Lehmann]

deprecation added in f3ed02b