`whenwasit path`  
little thing meant to be called in a git-hook as to keep track of
file creation and modification dates, which are important to me.
dumps csv output on stdout, errors abort with a panic.

**CSV Output Defintion:**  
data is output on `stdout` in a CSV format. because there are
varying ways to make a CSV, it's described in detail below.

- there is no data header; the first row is data
- the data rows are in the format `path,btime,mtime,atime`
	- `path`: file path relative to the root that was provided on the command line
	- `btime`: time of file creation; birth time
	- `mtime`: time file was last modified
	- `atime`: time file was last accessed
- if the `path` contains a comma (`,`) or a backslash (`\`), it is escape with a backslash
- if any one of the time cannot be attained, the field is left empty.

**behavior:**  
prints a row for the current directory, a row for each file, and
then goes into each directory recursively.

this results in reading the directory twice as to not cache the
directory listings in memory.