configurable zip compression

Have zip format honor compression-level.
Add Android AOSP Build System Makefile fragments and config files

add def guard for S_IRGRP which is defined in the AndroidConfig.h
system header
Merge pull request #96 from trevd/master

Add Android AOSP Build System Makefile fragments and config files
Merge branch 'patch-1' of https://github.com/vlovich/libarchive into vlovich-patch-1

Conflicts:
	libarchive/archive_write_set_format_zip.c

This was originally submitted as:
   https://github.com/libarchive/libarchive/pull/84

I've made the following corrections:
   * Added a new variable for the deflate compression level (the submitted patch mis-used the requested_compression variable)
   * Extended the Zip store format test to also verify correct results with compression-level=0

TODO: This really needs a new test to exercises non-zero compression-level options.
Merge branch 'vlovich-patch-1'
Fix typos in archive_pathmatch logic.

This was explored in pull request #78 by github user maksqwe.
After considering the alternatives, I think the existing
behavior was correct (but the comments were wrong and there was
extraneous code).  Extended tests to cover this case and some
other cases that were not fully exercised.
Merge branch 'upstream'
Replace swprintf to wcscpy+wcscat.

swprintf has different signatures on MinGW/MinGW-w64/MSVC.
Fix inconsistent structure declaration bug.