Usage:
sepolicy-analyze -D -P out/target/product/<board>/root/sepolicy

Displays duplicate allow rules, i.e. pairs of allow rules that grant
the same permissions where one allow rule is written directly in terms
of individual types and the other is written in terms of attributes
associated with those same types.  The rule with individual types is
a candidate for removal.  The rule with individual types may be directly
represented in the source policy or may be a result of expansion of
a type negation (e.g. domain -foo -bar is expanded to individual allow
rules by the policy compiler).  Domains with unconfineddomain will
typically have such duplicate rules as a natural side effect and can
be ignored.

Also add a tools/README with a description of all of the tools.

Change-Id: I07838dbd22c5cc8a4a65b57003ccae38129050f5
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>