Bug fix.

In statements like "for (String element : message.getBody().",
completion was not available.
Added #'ajc-parse-variable-line-string.

Factored out line-parsing part of
#'ajc-calculate-class-name-by-variable into
#'ajc-parse-variable-line-string.

Fixed a bug in #'ajc-line-has-typeinfo-p.

Added a variable named ajc-thing-after-varname-regexp.
Bug fix in #'ajc-find-out-matched-class-item-1.
Removed #'ajc-find-out-matched-class-item-1.

The reason is that when searching for a class-item, we don't have to
iterate througth tag-buffer-list. We just have to look into the tag
buffer specified by the index in matched package item.
Fixed some tests. Now all tests passes.