FIX add missing blank line between text and table

The markdown interpreter don't interpret the table otherwise.

googletest/docs/Primer.md

@@ -108,6 +108,7 @@ streamed to an assertion, it will be translated to UTF-8 when printed.
 ## Basic Assertions ##
 
 These assertions do basic true/false condition testing.
+
 | **Fatal assertion** | **Nonfatal assertion** | **Verifies** |
 |:--------------------|:-----------------------|:-------------|
 | `ASSERT_TRUE(`_condition_`)`;  | `EXPECT_TRUE(`_condition_`)`;   | _condition_ is true |
@@ -498,4 +499,4 @@ is currently _unsafe_ to use Google Test assertions from two threads
 concurrently on other systems (e.g. Windows).  In most tests this is
 not an issue as usually the assertions are done in the main thread. If
 you want to help, you can volunteer to implement the necessary
-synchronization primitives in `gtest-port.h` for your platform.
+synchronization primitives in `gtest-port.h` for your platform.