build: osx: Fix incomplete framework packaging for codesigning

Starting with 10.9, Framework versions must be signed individually, rather
than as a single bundle version, in order to be properly codesigned. This
change ensures that the proper plist files and symlinks are present prior to
packaging.
Make script_{valid,invalid}.json validation flags configurable
Stricter handling of orphan transactions

Prevent denial-of-service attacks by banning
peers that send us invalid orphan transactions
and only storing orphan transactions given to
us by a peer while the peer is connected.
Store fewer orphan tx by default, add -maxorphantx option

There is no reason to store thousands of orphan transactions;
normally an orphan's parents will either be broadcast or
mined reasonably quickly.

This pull drops the maximum number of orphans from 10,000 down
to 100, and adds a command-line option (-maxorphantx) that is
just like -maxorphanblocks to override the default.
Merge pull request #4885

aa3c697 Store fewer orphan tx by default, add -maxorphantx option (Gavin Andresen)
c74332c Stricter handling of orphan transactions (Gavin Andresen)
Catch error when done reading files
Merge pull request #4758 from theuni/osx-dmg-codesign-rebase

build: osx: Fix incomplete framework packaging for codesigning
Merge pull request #4876

6022b5d Make script_{valid,invalid}.json validation flags configurable (Pieter Wuille)
Merge pull request #4896

07d5287 Catch error when done reading files (Suhas Daftuar)
Create the common location for all m4 autotool build scripts, build-aux/m4.
Update .gitignore.