Rule 0302 should not consider special symbols

[hajdum]

Describe the bug
Rule 0302 should not consider special symbols such as - , = ....

To Reproduce
Steps to reproduce the behavior:

1. Create keyword with name: THIS-IS-MY-KEYWORD
2. run robot
3. observe

Expected behavior
0302 rule notification is not present

[bhirsz]

Valid point. There is also this problem that Robocop when analyzing the keyword does not know if the keyword have embedded variables. For example:

*** Keywords ***
My Keyword With ${var} Variable    # this is handled as we recognize we have variable here
    No Operation

Other Keyword
    My Keyword With small Variable  # this will throw warning

This could be somehow connected. But for rule 0302 I could try to strip any non letter character and then run check. Ie
THIS-IS-MY-KEYWORD -> THIS IS MY KEYWORD

Of course some characters are not desired in keyword name but it should not raise warning with 0302 (keyword not capitalized) but with other rule.

[bhirsz]

Example fix at fix/not_capitalized_special_chars branch

You can checkout this branch, install it from source code (pip install -e . if in roboframework-robocop directory) and use it for test.

I will spend some extra time thinking about best algorithm for this rule before merging anything