Add more validation on the UI field: artifactId

[IvoNet]

Add validation to the artifactId field in the starter UI

ArtifactId should only allow:

• lowercase names
• names starting with [a-z]
• hyphens ('-') but no underscores ('_')
• no spaces
• etc.

see also here: guide-naming-conventions

[geziefer]

I could do this together with #274

[geziefer]

groupId satisfies java package naming which must start with a letter followes by any number of letters, digits or underscore and then any number of similar parts separated by dot - the following regex was used: "^[a-zA-Z][a-zA-Z0-9_](.[a-zA-Z][a-zA-Z0-9_])*$"
This was addressed in PR #292

[m-reza-rahman]

Fixed.