Add srtp_set_user_data() and srtp_get_user_data() functions.
Merge pull request #66 from ibc/master

Add srtp_set_user_data() and srtp_get_user_data() functions.  Thanks for the contribution.
Remove config.h from public headers and include it in non-header files instead

To avoid symbol collision such as PACKAGE or VERSION with
autotools-based project.
Fix building with --enable-openssl after removed config.h inclusion from
public header files
Merge pull request #69 from teerapap/fix-autotools-config-h

Thanks for the contribution.
Fix compiler warning in unit test code.
build: define PACKAGE_NAME and PACKAGE_VERSION
build: add pkg-config file generation support
build: regenerate configure file
gitignore: ignore generated pkg-config file
Fix build breakage when stdint.h is included by application layer.
Include stdint and stddef in srtp.h to alleviate this requirement from the application layer.  Modified integers.h to only include the uint64_t redef when the SRTP config.h is included in the build, which should limit this to only when building libsrtp.a.  This prevents the redef from being used when the application layer includes srtp.h.
Fix build breakage at application layer when using g++.
Merge pull request #70 from saghul/pkg_config

Thanks for the contribution.