remove WAL from sqlite to avoid bugs

also log how long it took to load or synch a file

Why remove WAL?
It was faster yes, but often the engine would not have the up-to-date info and then crash.
Adding walcheckpoints all over the place didnt seem to help

the slowdown is a bit noticeable with >3000k columns, but given that we didnt support them before shouldnt be a big problem.

For speed comparisons:

        WAL     NO-WAL
3KC      4s        10s
10KC    28s        54s
200KR   30s        30s
1MR    146s       147s
1KR5KC 347s       356s

Where the "R" sets have 2 columns and the "C" sets have a single row.
As can be seen, there *is* a delay for 1K cols and above, but it seems constant.
And any fixes for the synching-db problem with the engine most likely includes adding new delays...
So lets just turn it off

CommonData/databaseinterface.cpp

@@ -1589,8 +1589,6 @@ void DatabaseInterface::create()
 	}
 	else
 		Log::log() << "Opened internal sqlite database for creation at '" << dbFile() << "'." << std::endl;
-
-	dbStartUpPragmas();
 
 	transactionWriteBegin();
 	runStatements(_dbConstructionSql);
@@ -1615,20 +1613,6 @@ void DatabaseInterface::load()
 	else
 		Log::log() << "Opened internal sqlite database for loading at '" << dbFile() << "'." << std::endl;
 
-	dbStartUpPragmas();
-}
-
-void DatabaseInterface::dbStartUpPragmas()
-{
-	runStatements("pragma journal_mode = WAL;");
-	runStatements("pragma synchronous = normal;");
-}
-
-
-void DatabaseInterface::doWALCheckpoint()
-{
-	// https://www.sqlite.org/pragma.html#pragma_wal_checkpoint
-	runStatements("PRAGMA wal_checkpoint(TRUNCATE);");
 }
 
 void DatabaseInterface::close()

CommonData/databaseinterface.h

@@ -158,10 +158,7 @@ class DatabaseInterface
 	void		transactionWriteEnd(bool rollback = false);		///< runs COMMIT or ROLLBACK based on rollback and ends the transaction.  Tracks whether nested and only does BEGIN+COMMIT at lowest depth
 	void		transactionReadBegin();							///< runs BEGIN DEFERRED and waits for sqlite to not be busy anymore if some other process is writing  Tracks whether nested and only does BEGIN+COMMIT at lowest depth
 	void		transactionReadEnd();							///< runs COMMIT and ends the transaction. Tracks whether nested and only does BEGIN+COMMIT at lowest depth
-
-	//WAL handling, was added in https://github.com/jasp-stats/jasp-desktop/commit/4cfe6197714440b0ab6936891fa5ff7cc8ac19b6, see docs: https://www.sqlite.org/wal.html
-	void		doWALCheckpoint(); ///< Writes all pending changes to the db-file
-
+
 private:
 	void		_doubleTroubleBinder(sqlite3_stmt *stmt, int param, double dbl);	///< Needed to work around the lack of support for NAN, INF and NEG_INF in sqlite, converts those to string to make use of sqlite flexibility
 	double		_doubleTroubleReader(sqlite3_stmt *stmt, int colI);					///< The reading counterpart to _doubleTroubleBinder to convert string representations of NAN, INF and NEG_INF back to double
@@ -172,7 +169,6 @@ class DatabaseInterface
 	void		load();											///< Loads a sqlite database from sessiondir (after loading a jaspfile)
 	void		close();										///< Closes the loaded database and disconnects
 	bool		tableHasColumn(const std::string & tableName, const std::string & columnName);
-	void		dbStartUpPragmas();
 
 	int			_transactionWriteDepth	= 0,
 				_transactionReadDepth	= 0;

Desktop/data/exporters/jaspexporter.cpp

@@ -163,6 +163,5 @@ void JASPExporter::saveAnalyses(archive *a)
 
 void JASPExporter::saveDatabase(archive * a)
 {
-	DatabaseInterface::singleton()->doWALCheckpoint();
 	saveTempFile(a, DatabaseInterface::singleton()->dbFile(true));
 }

Desktop/data/importers/csvimporter.cpp

@@ -30,7 +30,7 @@ CSVImporter::CSVImporter() : Importer()
 ImportDataSet* CSVImporter::loadFile(const string &locator, std::function<void(int)> progressCallback)
 {
 	JASPTIMER_RESUME(CSVImporter::loadFile);
-
+	
 	ImportDataSet* result = new ImportDataSet(this);
 	stringvec colNames;
 	CSV csv(locator);

Desktop/data/importers/importer.cpp

@@ -15,6 +15,8 @@ Importer::~Importer() {}
 
 void Importer::loadDataSet(const std::string &locator, std::function<void(int)> progressCallback)
 {
+	long timeBeginS = Utils::currentSeconds();
+
 	DataSetPackage::pkg()->beginLoadingData();
 
 	_synching = false;
@@ -52,6 +54,9 @@ void Importer::loadDataSet(const std::string &locator, std::function<void(int)>
 	importDataSet->clearColumns();
 	delete importDataSet;
 	DataSetPackage::pkg()->endLoadingData();
+
+	long totalS = (Utils::currentSeconds() - timeBeginS);
+	Log::log() << "Loading '" << locator << "' took " << totalS << "s or " << (totalS / 60) << "m" << std::endl;
 }
 
 void Importer::initColumn(QVariant colId, ImportColumn *importColumn)
@@ -73,6 +78,7 @@ void Importer::initColumnWithStrings(QVariant colId, const std::string &newName,
 void Importer::syncDataSet(const std::string &locator, std::function<void(int)> progress)
 {
 	_synching = true;
+	long timeBeginS = Utils::currentSeconds();
 
 	ImportDataSet *	importDataSet	= loadFile(locator, progress);
 	bool			rowCountChanged	= importDataSet->rowCount() != DataSetPackage::pkg()->dataRowCount();
@@ -135,6 +141,9 @@ void Importer::syncDataSet(const std::string &locator, std::function<void(int)>
 
 	DataSetPackage::pkg()->setManualEdits(false);
 	delete importDataSet;
+
+	long totalS = (Utils::currentSeconds() - timeBeginS);
+	Log::log() << "Synching '" << locator << "' took " << totalS << "s or " << (totalS / 60) << "m" << std::endl;
 }
 
 void Importer::_syncPackage(