As indentation is a very handy way to structure comments and increase
their readability as much of it as possible should be preserved.
This removes any trimming of leading white spaces and ensures that
any cbindgen annotations are still recognized afterwards.
... fixes#184
Rustc already removes all leading `/` symbols during the conversion
from doc-comments into annotations. Any additional trimming of non
whitespace characters just reduces the formatting flexibility of a
comment.
... fixes#374
This required two changes in parallel.
As a first and obvious step it removes a check that skipped emptys
lines during documentation loading, but it was also necessary to
refactore the `get_comment_lines()` utility method as a second step.
This second refactoring was necessary as each line in a doc comment
is trimmed and transformed in its own doc attribute. The attribute
of an empty line therefore contains an empty string as value. If we
now call `lines()` on such an empty string we end up with an empty
iterator as the method is internally configured to ignore trailing
empty lines.