Add a description of the package format

PACKAGES.md

@@ -0,0 +1,43 @@
+Pkg package format
+==================
+
+*Pkg* is the name of Shrine's package manager.
+
+Each package ships as a manifest + one or more download formats.
+The only download format currently supported is RedSea disk image (.ISO.C)
+
+Manifest format
+---------------
+
+The manifest is a key-value format, using exactly one Tab character as delimiter. The keys are:
+
+ - `osmin` (int - minimum supported OS version, default 0)
+ - `osmax` (int - maximum OS version, default *+∞*)
+ - `pkgmin` (int - minimum *Pkg* version, default *+∞*)
+ - `version` (string up to 6 chars - version for display purposes, default *NULL*)
+ - `release` (int - version for comparison purposes, default 0)
+ - `installdir` (string, default *NULL*)
+ - `iso.c` (string - see below, default *NULL*)
+ - `size` (int - download size in bytes, default 0)
+
+Currently ignored keys:
+
+ - `name` (string - package name)
+ - `website` (string)
+
+For a package to be installable, it needs to specify at least `pkgmin`, `version`, `installdir` and a downloadable file.
+The manifest can contain any other keys; *Pkg* might or might not preserve them.
+
+`iso.c` changes meaning depending on the context.
+This is somewhat confusing, which makes it a perfect fit for TempleOS.
+
+- in repo, it's a (usually relative) URL to the package's ISO.C download
+- in a downloaded package it is a filesystem path
+- when building a package it specifies the output filename
+
+`size` is ambiguous if the package provides multiple download formats. It's not a big deal.
+
+Dependency resolution
+---------------------
+
+Soon!

README.md

@@ -58,6 +58,8 @@ Note: In Lsh, use `pkg-install xyz` in place of `PkgInstall("xyz")` etc.
 
   Build a package from a single file. See above for details.
 
+[See here](PACKAGES.md) for more information about how packages work.
+
 Building from source
 ====================
 

Shrine/Packages/Pkg/Pkg.HC

@@ -322,7 +322,6 @@ I64 PkgInstall(U8* package_name) {
       "$FG,8$  Package              Ver   \n"
       "$FG,8$  Dir                  Size  \n"
       "$FG,8$============================\n"
-      "$FG,7$Install:\n";
       "$FG,2$+ %-20s %-6s\n", package_name, pinf.version;
       "$FG,2$  %-20s %-6s\n", pinf.installdir, FormatSize(pinf.size);
       "\n"