[FL-872] Furi, API-HAL, App-Loader cleanup and improvements (#334)

* Furi: replace obsolete furiac_exit with osThreadExit, drop obsolete apis and test. Rename systemd to flipper and move to separate file, cleanup. ApiHal: Rename timebase to os and move freertos hooks there, move insomnia api to power module.
* Furi: new thread helper
* Furi: cleanup thread documentation
* Flipper, AppLoader: update to use FuriThread. Update tasks signatures to match FuriThreadCallback signature.
* F4: rename API_HAL_TIMEBASE_DEBUG to API_HAL_OS_DEBUG
* Applications: rename FuriApplication to FlipperApplication, use FuriThreadCallback signature for apps.
* C++ app template sample, new exit method

core/furi/thread.h

@@ -0,0 +1,102 @@
+#pragma once
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <cmsis_os2.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* FuriThreadState */
+typedef enum {
+    FuriThreadStateStopped,
+    FuriThreadStateStarting,
+    FuriThreadStateRunning,
+} FuriThreadState;
+
+/* FuriThread anonymous structure */
+typedef struct FuriThread FuriThread;
+
+/* FuriThreadCallback
+ * Your callback to run in new thread
+ * @warning don't use osThreadExit
+ */
+typedef int32_t (*FuriThreadCallback)(void* context);
+
+/* FuriThread state change calback
+ * called upon thread state change
+ * @param state - new thread state
+ * @param context - callback context
+ */
+typedef void (*FuriThreadStateCallback)(FuriThreadState state, void* context);
+
+/* Allocate FuriThread
+ * @return FuriThread instance
+ */
+FuriThread* furi_thread_alloc();
+
+/* Release FuriThread
+ * @param thread - FuriThread instance
+ */
+void furi_thread_free(FuriThread* thread);
+
+/* Set FuriThread name
+ * @param thread - FuriThread instance
+ * @param name - string
+ */
+void furi_thread_set_name(FuriThread* thread, const char* name);
+
+/* Set FuriThread stack size
+ * @param thread - FuriThread instance
+ * @param stack_size - stack size in bytes
+ */
+void furi_thread_set_stack_size(FuriThread* thread, size_t stack_size);
+
+/* Set FuriThread callback
+ * @param thread - FuriThread instance
+ * @param callback - FuriThreadCallback, called upon thread run
+ */
+void furi_thread_set_callback(FuriThread* thread, FuriThreadCallback callback);
+
+/* Set FuriThread context
+ * @param thread - FuriThread instance
+ * @param context - pointer to context for thread callback
+ */
+void furi_thread_set_context(FuriThread* thread, void* context);
+
+/* Set FuriThread state change callback
+ * @param thread - FuriThread instance
+ * @param callack - state change callback
+ */
+void furi_thread_set_state_callback(FuriThread* thread, FuriThreadStateCallback callback);
+
+/* Set FuriThread state change context
+ * @param thread - FuriThread instance
+ * @param context - pointer to context
+ */
+void furi_thread_set_state_context(FuriThread* thread, void* context);
+
+/* Start FuriThread
+ * @param thread - FuriThread instance
+ * @return true on success
+ */
+bool furi_thread_start(FuriThread* thread);
+
+/* Treminate FuriThread
+ * @param thread - FuriThread instance
+ * @return osStatus_t
+ * @warning terminating statefull thread is dangerous
+ * use only if you know what you doing
+ */
+osStatus_t furi_thread_terminate(FuriThread* thread);
+
+/* Join FuriThread
+ * @param thread - FuriThread instance
+ * @return osStatus_t
+ */
+osStatus_t furi_thread_join(FuriThread* thread);
+
+#ifdef __cplusplus
+}
+#endif