#129 Check RegExp in input fields

[Anonymous]

When a RegExp is wrong It is difficult to know where the error originated, being that most of the times an exception is given in the error log.
It'd be nice to have the RegExp directly validated in the input fields.

Or at least tell the user in which rule the exception was thrown.

Thanks!

[Lars Koedderitzsch]

Feature already exists, except for some special corner cases like RegexpHeader.