Enable third party contributions

- Add instructions for contributing to ARM Trusted Firmware.

- Update copyright text in all files to acknowledge contributors.

Change-Id: I9311aac81b00c6c167d2f8c889aea403b84450e5
diff --git a/common/bl_common.c b/common/bl_common.c
index d125786..8183337 100644
--- a/common/bl_common.c
+++ b/common/bl_common.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, ARM Limited. All rights reserved.
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/common/psci/psci_afflvl_off.c b/common/psci/psci_afflvl_off.c
index 937ba9d..fea2b7e 100644
--- a/common/psci/psci_afflvl_off.c
+++ b/common/psci/psci_afflvl_off.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, ARM Limited. All rights reserved.
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/common/psci/psci_afflvl_on.c b/common/psci/psci_afflvl_on.c
index b0de063..7126b98 100644
--- a/common/psci/psci_afflvl_on.c
+++ b/common/psci/psci_afflvl_on.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, ARM Limited. All rights reserved.
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/common/psci/psci_afflvl_suspend.c b/common/psci/psci_afflvl_suspend.c
index 9a2c0cf..b68b4df 100644
--- a/common/psci/psci_afflvl_suspend.c
+++ b/common/psci/psci_afflvl_suspend.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, ARM Limited. All rights reserved.
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/common/psci/psci_common.c b/common/psci/psci_common.c
index 6b07c53..59126ba 100644
--- a/common/psci/psci_common.c
+++ b/common/psci/psci_common.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, ARM Limited. All rights reserved.
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/common/psci/psci_entry.S b/common/psci/psci_entry.S
index 014e4cf..2f39f36 100644
--- a/common/psci/psci_entry.S
+++ b/common/psci/psci_entry.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, ARM Limited. All rights reserved.
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/common/psci/psci_main.c b/common/psci/psci_main.c
index eca2dec..b1aa899 100644
--- a/common/psci/psci_main.c
+++ b/common/psci/psci_main.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, ARM Limited. All rights reserved.
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/common/psci/psci_private.h b/common/psci/psci_private.h
index 6505adf..4741397 100644
--- a/common/psci/psci_private.h
+++ b/common/psci/psci_private.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, ARM Limited. All rights reserved.
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/common/psci/psci_setup.c b/common/psci/psci_setup.c
index 9095e75..8220b30 100644
--- a/common/psci/psci_setup.c
+++ b/common/psci/psci_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, ARM Limited. All rights reserved.
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
diff --git a/common/runtime_svc.c b/common/runtime_svc.c
index ed1225f..0aa4460 100644
--- a/common/runtime_svc.c
+++ b/common/runtime_svc.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, ARM Limited. All rights reserved.
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met: