code: public boolean startsWith(Text pattern) {
      	if (pattern == null) {
      		return false;
      	}
      	return this.subSequence(0, pattern.len).equals(pattern);
      }
docs: Indicates whether the text starts with a certain pattern.
  
  @param pattern
  The pattern to match
  @return <code>true</code> if this text starts with the pattern.
  Otherwise, or if the pattern is null, returns <code>false</code>.
  @author hrosa