Handle shebang line, plus any whitespace and comment skipping in lexer

The lexer tried to handle the shebang line but used loc directly,
instead of the current_column. And it assumed a '/' should immediately
follow the "#!". But if the "#!" is followed by whitespace and/or
comments and a '[' character, then the first line isn't see as a
shebang line (even if the kernel or shell would) but as the start of
an inner attribute.

Add various tests for when the first line starting with "#!" is seen
as a shebang line (and should be skipped). And some tests there is a
'[' character following some whitespace and/or comments and the "#!"
is seen as part of an inner attribute.

0 files changed, 0 insertions, 0 deletions