Add setting for command style

[nigelcharman]

Currently the plugin includes both the camel cased and spinal cased variants of commands. For example c:assertEquals or c:assert-equals:

This makes the list longer, with more to read and select from.

I suggest we add a setting to choose either camel or spinal case, then only show the commands in that case. The default should be spinal-case, since camel case is not strictly valid XHTML.

[idegtiarenko]

Configuration of concordion command case added to Settings > Languages % Frameworkds > Concordion

Completion will contain only configured case

Inspection added to report usages of wrong command case

Quick fix is introduced