update typo in build.php; update docs

docs/80_Build.md

@@ -7,6 +7,16 @@
 </html>
 <!-- END-ADD-TTY-PLAYER -->
 
+## Introduction
+
+The compilation to a platform specific binary is done with `spc`.
+
+Website: <https://static-php.dev/>
+
+We need to prepare an environment to let do it its work.
+
+Additionally you need a PHP installation to modify php sources and to start installer and build script.
+
 ## Requirements
 
 ### Linux
@@ -60,7 +70,7 @@ You get this initial structure:
 
 ### Installer
 
-Run the `./installer.php` to download apmonitor source and spc. It prepares the micro build and creates a merged php file of all appmonitor client checks. This script has command line parameter support.
+Run the `./installer.php` to download IML Appmonitor source and spc. It prepares the micro build and creates a merged php file of all appmonitor client checks. This script has command line parameter support.
 
 ```txt
 ./installer.php -h
@@ -137,7 +147,7 @@ To build the amcli binary start `./build.php`. This script has command line para
     - Merge PHP sources to a single file
     - Compile binary
     - Test binary
-    - Coy to architecture specific binary
+    - Copy to architecture specific binary
     - Create readme with buildinfos
 
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