Move tests to relevant subprojects (#615)

- Moved test projects to the parent project they belong to
- Improved test stability/corectness
- Improved recursive directory deletion by safely ignoring current- and parent-directory entries.
- Update docs

Tactility/Tests/Source/TestFile.h

@@ -0,0 +1,42 @@
+#pragma once
+
+#include "doctest.h"
+#include <unistd.h>
+
+#include <Tactility/file/File.h>
+
+/**
+ * A class for creating test files that can automatically clean themselves up.
+ */
+class TestFile {
+    const char* path;
+    bool autoClean;
+
+public:
+
+    TestFile(const char* path, bool autoClean = true) : path(path), autoClean(autoClean) {
+        if (autoClean && exists()) {
+            remove();
+        }
+    }
+
+    ~TestFile() {
+        if (autoClean && exists()) {
+            remove();
+        }
+    }
+
+    const char* getPath() const { return path; }
+
+    void writeData(const char* data) const {
+        CHECK_EQ(tt::file::writeString(path, data), true);
+    }
+
+    bool exists() const {
+        return access(path, F_OK) == 0;
+    }
+
+    void remove() const {
+        ::remove(path);
+    }
+};