binfmt-detector-cli: rewrite to support PE32+ binaries (#38)

Rewrite with hard-coded offsets into the PE file format to discern
if a binary is PE32 or PE32+, and then to determine if it contains
a "CLR Data Directory" entry that looks valid.

Tested with PE32 and PE32+ compiled Mono binaries, PE32 and PE32+ native
binaries, and a random assortment of garbage files.

Former-commit-id: 9e7ac86ec84f653a2f79b87183efd5b0ebda001b

external/helix-binaries/Microsoft.Data.Edm.dll.REMOVED.git-id

@@ -1 +0,0 @@
-6f797250b687221674a33462f05c741ff07bacbc

external/helix-binaries/Microsoft.Data.OData.dll.REMOVED.git-id

@@ -1 +0,0 @@
-300cf23dfe669d71e8cdbcb125454909f2657f24

external/helix-binaries/Microsoft.DotNet.Helix.Client.dll.REMOVED.git-id

@@ -1 +0,0 @@
-6422e36e91bccb63b4c7062dc498913f2bef8adb

external/helix-binaries/Microsoft.WindowsAzure.Storage.dll.REMOVED.git-id

@@ -1 +0,0 @@
-3a53c45dc0cfa0f36154025d4618fbf40bccba56

external/helix-binaries/Newtonsoft.Json.dll.REMOVED.git-id

@@ -1 +0,0 @@
-e2118f9b9c68453083213592eee7791980c67f4e

external/helix-binaries/System.Spatial.dll.REMOVED.git-id

@@ -1 +0,0 @@
-eb219984377baa73ec720dac5e01dff6825c6fa8