Fix problems that occurred when multiple threads were trying to read/convert files at the same time (ie: indexing and previewing threads in the GUI calling internfile()). Either get rid of or lock-protect all shared data, eliminate misc initialization possible conflicts by using static initializers. Hopefuly closes issue #51

src/rcldb/rcldb.cpp

@@ -80,7 +80,7 @@ string version_string(){
 
 // Synthetic abstract marker (to discriminate from abstract actually
 // found in document)
-const static string rclSyntAbs("?!#@");
+static const string rclSyntAbs("?!#@");
 
 // Compute the unique term used to link documents to their origin. 
 // "Q" + external udi

src/rcldb/stemdb.cpp

@@ -38,7 +38,7 @@ namespace Rcl {
 namespace StemDb {
 
 
-const static string stemdirstem = "stem_";
+static const string stemdirstem = "stem_";
 
 /// Compute name of stem db for given base database and language
 static string stemdbname(const string& dbdir, const string& lang)