Fix Markdown fails to parse lines with leading spaces

[MohamedRejeb]

Fixes: #443

[Wavesonics]

@MohamedRejeb I'm not quite sure, but I think this fix is maybe not what we want? I think we want to preserve the leading spaces, as an indent. This appears to strip all leading spaces, preventing us from being able to indent a line.

[Wavesonics]

never mind, I did a little reading and I guess the baseline markdown spec doesn't actually support indenting a normal line of text.

if you want an indentation you're supposed to use &nbsp or >