Resolve "static attributes prevent more than one validation"

Closes #18

See merge request RiseClipseGroup/RiseClipseValidator_SCL2003!18

Merge branch '17-if-output-is-the-last-option-the-output-file-is-also-considered-as-an-scl-file' into 'master'

Resolve "if --output is the last option, the output file is also considered as an SCL file"

Closes #17

See merge request RiseClipseGroup/RiseClipseValidator_SCL2003!17

Resolve "give option to output messages in a file"

Closes #16

See merge request RiseClipseGroup/RiseClipseValidator_SCL2003!16

Resolve "some line number in message are missing"

Closes #15

See merge request RiseClipseGroup/RiseClipseValidator_SCL2003!15

Resolve "update HMI from previous version to allow for loading NSD files"

Closes #14

See merge request RiseClipseGroup/RiseClipseValidator_SCL2003!14

Resolve "enumeration name may differ"

Closes #13

See merge request RiseClipseGroup/RiseClipseValidator_SCL2003!13

Resolve "update displayed version for tool diffusion"

Closes #12

See merge request RiseClipseGroup/RiseClipseValidator_SCL2003!12

Resolve "complete validation by NSD"

NSD validation is not completely done, but it is enough advanced so that next steps will be done in individual issue/merge request

Closes #11

See merge request RiseClipseGroup/RiseClipseValidator_SCL2003!11

to avoid much of duplicated code.
Not yet done for DataObjectPresenceCondiitonValidator.