DOC: assorted typo fixes in the documentation and Makefile

This is another round of cleanups in various docs and comments in the
Makefile.

(cherry picked from commit 2a950d02a951715447d4068ec6689a842d452aaa)
Signed-off-by: Willy Tarreau <w@1wt.eu>
(cherry picked from commit 99ac71d7fff3cc11d70fb2de2758daf69cd85e42)
[wt: drop changes not for 2.0]
Signed-off-by: Willy Tarreau <w@1wt.eu>
diff --git a/INSTALL b/INSTALL
index 84548df..f65bc51 100644
--- a/INSTALL
+++ b/INSTALL
@@ -130,7 +130,7 @@
 HAProxy in its basic form does not depend on anything beyond a working libc.
 However a number of options are enabled by default, or are highly recommended,
 and these options will typically involve some external components or libraries,
-depending on the targetted platform.
+depending on the targeted platform.
 
 Optional dependencies may be split into several categories :
 
@@ -288,7 +288,7 @@
 
 4.7) Lua
 --------
-Lua is an embedded programming langage supported by HAProxy to provide more
+Lua is an embedded programming language supported by HAProxy to provide more
 advanced scripting capabilities. Only versions 5.3 and above are supported.
 In order to enable Lua support, please specify "USE_LUA=1" on the command line.
 Some systems provide this library under various names to avoid conflicts with