Add exclude_files and exclude_dirs properties to java_import

Prebuilt jars sometime contain files that we don't want.  In Make
we would delete everything in META-INF when importing jars, but
that caused problems when there were necessary files in there,
so we added LOCAL_DONT_DELETE_JAR_META_INF.

Soong does the opposite, keeping everything by default.  Add
properties to allow explicitly stripping unwanted files instead.

Bug: 111389216
Test: m checkbuild
Change-Id: I6d07f519ebc7d0e1bf0af93416bb569e3c2b1500