Docs: No EOL Whitespaces

End-of-line (EOL) whitespaces are verbose and increase diffs and
merge conflicts over time.

There is a notable exception to this rule, as two EOL white spaces
in Markdown (`.md`) files introduce a soft-break (newline without
paragraph).

Cleaned them up for the `Docs/` directory with the following bash
one-liner:

```bash
find . -type f -not -path './.git*'  \
  -exec sed -i 's/[[:blank:]]*$//' {} \;
```

Committed as generic user so git does not credit the many lines
to me:
```bash
GIT_AUTHOR_NAME="Tools" GIT_AUTHOR_EMAIL="warpx@lbl.gov"  \
  git commit
```

0 files changed, 0 insertions, 0 deletions