(fixes #26)

(fixes #106)

protoc-c/c_enum.cc: fix compiler warnings
protoc-c/c_field.cc: fix compiler warnings

Signed-off-by: Dave Benson <lahiker42@gmail.com>

better compatibility with 8- and 16-bit platforms (integrate fixes
from #47)

protobuf_c_dispatch_close_fd() (fixes #82)

check for server closures (responses) to not crash the server in case of
a malformed message (related to #76)

protobuf_c_message_check

leave a dangling pointer to the parsed submessage

test_field_merge

of the same field on the wire (Fixes #91)
t/generated-code2/test-generated-code2.c: add a test case for merging
messages
t/test-full.proto: expand message definitions to test for merging nested
messages

this simplifies the AC_C_BIGENDIAN invocation.

PACKAGE_STRING provided by autotools (fixes #52)

in case the client has failed to connect and got destroyed (fixes #70)

protobuf-c-rpc/t/test-rpc.c: add a test case for #70

messages on the client side (fixes #78)

protobuf-c-rpc/t/test-rpc.c: add a test case for #78

per https://code.google.com/p/protobuf/source/detail?r=50, the license
on google-originated protobuf code was switched from Apache-2.0 to
BSD-3-Clause (so-called "New BSD" license). update any of the google
license statements to use this new license.

per email with dave, drop the third clause on his BSD-3-Clause license,
so this now becomes BSD-2-Clause.

make sure to use consistent indentation and wrapping throughout.

the change that required protobuf >= 2.5.0 has been reverted, so there's
no need to build protobuf from source. use the system protobuf packages
instead.

also use distcheck to build and check the distribution. this will run
the test suite and perform various other checks. it will also perform a
VPATH build using the distribution tarball, which will catch any files
present in the git repository but inadvertently not distributed in the
tarball.

also test the build when configured with "--enable-rpc".