Fix RST rendering typos and broken links

Change-Id: I40631d9c1d99e24311d158cec5a47b433d6fe328
Signed-off-by: John Tsichritzis <john.tsichritzis@arm.com>
diff --git a/docs/design.rst b/docs/design.rst
index a59c1d7..e10b553 100644
--- a/docs/design.rst
+++ b/docs/design.rst
@@ -76,8 +76,10 @@
 
 -  **Library code.**
 
-   Some examples of APIs provided in ``include/lib/`` follow, this list might
-   not be exhaustive.
+   Firstly, there is ``include/stdlib/`` which provides standard C library
+   functions like ``memcpy()``, ``printf()`` and so on.
+   Additionally, various other APIs are provided under ``include/lib/``. The
+   below list gives some examples but might not be exhaustive.
 
    -  ``aarch64/``
 
@@ -129,9 +131,6 @@
       directly. They should use higher-level APIs like ``tftf_nvm_read()``
       and ``tftf_nvm_write()``.
 
-  ``include/stdlib/`` provides standard C library functions (``memcpy()``,
-  ``printf()``, and so on).
-
 -  **Platform specific.**
 
    Note that ``include/plat/common/plat_topology.h`` provides the interfaces
@@ -262,5 +261,5 @@
 
 *Copyright (c) 2018, Arm Limited. All rights reserved.*
 
-.. _Summary of build options: user-guide.html#summary-of-build-options
+.. _Summary of build options: user-guide.rst#summary-of-build-options
 .. _Firmware Update: https://github.com/ARM-software/arm-trusted-firmware/blob/master/docs/firmware-update.rst