scspell should support directory traversal

[cassella]

I think it'd be handy for scspell to have directory-recursing
abilities. By way of illustration, here's my attempt at it for one
project:

https://github.com/chapel-lang/chapel/blob/master/util/chplspell

All the complexity of that script is in service of two user
conveniences:

1. The script has a built in default set of directories and file globs
   to search for within them, and

2. If any files or directories are given on the command line, they are
   used as the base of the search instead of the default ones.

This way, the user can just type chplspell and get all the right
files in the tree spell-checked, with the right dictionaries and
options.

If this functionality were moved inside scspell, then this script
could be replaced by effectively a one-liner, invoking scspell with a
description of those defaults and passing through the rest of the
commandline. And then any other projects that want to use scspell in
a similar manner would only need their own similar one-liner instead
of a complex script.

I don't know what would be the best interface for that. The two
alternatives I've thought of are:

1. Pass everything as commandline arguments.
2. Pass everything through a config file.

In the first alternative, that "one-liner" would be a very long line,
like the following (more generic files and directories than in the
above script):

#!/bin/bash
exec scspell --defdir doc --defdir man --defdir src \
             --defglob "*.c" --defglob "*.h" --defglob "*.cpp" \
             --use-builtin-base-dict \
             --relative-to $PROJ_HOME \
             --override-dictionary $PROJ_HOME/.scspell/dictionary \
             "$@"

In the second alternative, it would be a simpler one-liner. The
config file would specify all the other options from the command line
above.

#!/bin/bash
exec scspell --project-config $PROJ_HOME/.scspell/$PROJ.scspell.conf "$@"

Presumably using ConfigParser.

I'm not sure how to cleanly associate certain of the globs
(e.g. .tex) with certain behavior (e.g. --no-c-escapes). I could
imagine --deftexglob ".tex", but in addition to being a little gross,
it'd get grosser if there turn out to be languages that need their own
--no-c-escapes sort of switch. (The above script gets away with
includeing README* in default globs, and *.tex in the latex globs only
because there's no README.tex in tree.)

Thoughts?

[myint]

I suppose the config approach seems cleaner. And it seems that it could provide a better solution for associating globs. Or if not better, at least it would hide away the complexity from the command line options.

You're closer to this use case, so I'll leave it up to you.

[ifrh]

Is directory traversal a working feature in master branch of myint/scspell ?
Perhaps not, since #36 is not merged and has conflicts ...

@myint @dhruvsomani : Will this feature become functional in master?