Update assert_writeln_magic & dpl-docs to the latest libdparse

I noticed on the CI that this was throwing a lot of errors.
Turns out it was using a libdparse from late 2017,
which didn't knew about a lot of syntax changes,
such as 'body' -> 'do', new contract syntax, extern(C++, string)...

The two small changes required were introduced by:
- dlang-community/libdparse@daa93a5#diff-277d73641e4843decd9c9a41c6c23046L820
- dlang-community/libdparse@e625d2b#diff-ad149e8970c93d472185f0fb76ffcaeaR86

Author: Geod24

ddoc/dub.sdl

@@ -1,6 +1,6 @@
 name "ddoc_preprocessor"
 description "Preprocesses source code before running Ddoc over it"
-dependency "libdparse" version="~>0.8.7"
+dependency "libdparse" version="~>0.15.1"
 dependency "dmd" path="../../dmd"
 versions "DdocOptions"
 buildRequirements "disallowDeprecations"

ddoc/dub.selections.json

@@ -2,7 +2,7 @@
 	"fileVersion": 1,
 	"versions": {
 		"dmd": {"path":"../../dmd"},
-		"libdparse": "0.8.7",
-		"stdx-allocator": "2.77.2"
+		"libdparse": "0.15.4",
+		"stdx-allocator": "2.77.5"
 	}
 }

ddoc/source/assert_writeln_magic.d

@@ -1,6 +1,6 @@
 #!/usr/bin/env dub
 /++ dub.sdl:
-dependency "libdparse" version="0.7.2-alpha.4"
+dependency "libdparse" version="0.15.1"
 name "assert_writeln_magic"
 +/
 /*
@@ -76,7 +76,8 @@ class TestVisitor(Out) : ASTVisitor
             return;
 
         // only look at `a == b` within the AssertExpression
-        if (typeid(expr.assertion) != typeid(CmpExpression))
+        if (!expr.assertArguments ||
+            typeid(expr.assertArguments.assertion) != typeid(CmpExpression))
             return;
 
         lastAssert = expr;
@@ -180,15 +181,15 @@ private:
 void parseString(Visitor)(ubyte[] sourceCode, Visitor visitor)
 {
     import dparse.lexer;
-    import dparse.parser : parseModule;
+    import dparse.parser : parseModule, ParserConfig;
     import dparse.rollback_allocator : RollbackAllocator;
 
     LexerConfig config;
     auto cache = StringCache(StringCache.defaultBucketCount);
     const(Token)[] tokens = getTokensForParser(sourceCode, config, &cache).array;
 
     RollbackAllocator rba;
-    auto m = parseModule(tokens, "magic.d", &rba);
+    auto m = parseModule(ParserConfig(tokens, "magic.d", &rba));
     visitor.visit(m);
 }
 

dpl-docs/dub.selections.json

@@ -1,23 +1,23 @@
 {
 	"fileVersion": 1,
 	"versions": {
-		"botan": "1.12.10",
+		"botan": "1.12.18",
 		"botan-math": "1.0.3",
 		"ddoc_preprocessor": {"path":"../ddoc"},
-		"ddox": "0.16.11",
-		"diet-ng": "1.5.0",
+		"ddox": "0.16.15",
+		"diet-ng": "1.7.2",
 		"dmd": {"path":"../../dmd"},
-		"eventcore": "0.8.35",
-		"hyphenate": "1.1.1",
-		"libasync": "0.8.3",
-		"libdparse": "0.8.7",
+		"eventcore": "0.9.7",
+		"hyphenate": "1.1.2",
+		"libasync": "0.8.6",
+		"libdparse": "0.15.4",
 		"libevent": "2.0.2+2.0.16",
-		"memutils": "0.4.11",
-		"mir-linux-kernel": "1.0.0",
+		"memutils": "1.0.4",
+		"mir-linux-kernel": "1.0.1",
 		"openssl": "1.1.6+1.0.1g",
-		"stdx-allocator": "2.77.2",
-		"taggedalgebraic": "0.10.11",
-		"vibe-core": "1.4.0",
-		"vibe-d": "0.8.4"
+		"stdx-allocator": "2.77.5",
+		"taggedalgebraic": "0.11.16",
+		"vibe-core": "1.9.3",
+		"vibe-d": "0.9.0"
 	}
 }