lint add dots

Author: ehsanmok

src/how-to-build-and-run.md

@@ -58,19 +58,19 @@ internally. The result is the compiling `rustc` is done in stages.
 - **Stage 0:** the stage0 compiler can be your existing
   (perhaps older version of)
   Rust compiler, the current _beta_ compiler or you may download the binary
-  from the internet
+  from the internet.
 - **Stage 1:** the code in your clone (for new version)
   is then compiled with the stage0
   compiler to produce the stage1 compiler.
   However, it was built with an older compiler (stage0),
-  so to optimize the stage1 compiler we go to next stage
+  so to optimize the stage1 compiler we go to next stage.
 - **Stage 2:** we rebuild our stage1 compiler with itself
   to produce the stage2 compiler (i.e. it builds
-  itself) to have all the _latest optimizations_
+  itself) to have all the _latest optimizations_.
 - _(Optional)_ **Stage 3**: to sanity check of our new compiler,
   we can build it again
   with stage2 compiler which must be identical to itself,
-  unless something has broken
+  unless something has broken.
 
 For hacking, often building the stage 1 compiler is enough, but for
 final testing and release, the stage 2 compiler is used.