Update Colvars library to version 2023-05-01

This update consists exclusively of bugfixes or maintenance-related changes.

The following is a list of pull requests in the Colvars repository since the previous update to LAMMPS:

- 532 Add XYZ trajectory reading feature
  https://github.com/Colvars/colvars/pull/532 (@jhenin, @giacomofiorin)

- 531 Delete objects quietly, unless explicitly requested via script (including VMD)
  https://github.com/Colvars/colvars/pull/531 (@giacomofiorin)

- 530 Append newline to log and error messages if not already present
  https://github.com/Colvars/colvars/pull/530 (@giacomofiorin)

- 528 Forward-declare OpenMP lock
  https://github.com/Colvars/colvars/pull/528 (@giacomofiorin)

- 527 Remove unneeded STL container
  https://github.com/Colvars/colvars/pull/527 (@giacomofiorin)

- 526 Allow collecting configuration files and strings before setting up interface
  https://github.com/Colvars/colvars/pull/526 (@giacomofiorin, @jhenin)

- 523 Fallback to linearCombination when customFunction is missing in customColvar
  https://github.com/Colvars/colvars/pull/523 (@HanatoK, @giacomofiorin)

- 522 Use iostream::fail() to check for I/O error
  https://github.com/Colvars/colvars/pull/522 (@jhenin)

- 520 Fix ref count
  https://github.com/Colvars/colvars/pull/520 (@giacomofiorin)

- 513 Set target temperature through a common code path
  https://github.com/Colvars/colvars/pull/513 (@giacomofiorin, @jhenin)

- 509 Safer detection of Windows with recent Microsoft Visual Studio versions
  https://github.com/Colvars/colvars/pull/509 (@akohlmey)

- 508 Update LAMMPS patching method to reflect Lepton availability
  https://github.com/Colvars/colvars/pull/508 (@giacomofiorin)

- 497 Increase the precision of write_multicol
  https://github.com/Colvars/colvars/pull/497 (@HanatoK)

- 496 Only perform MTS automatic enable/disable for timeStepFactor > 1
  https://github.com/Colvars/colvars/pull/496 (@giacomofiorin)

- 493 Remove unused branch of quaternion input function
  https://github.com/Colvars/colvars/pull/493 (@giacomofiorin)

- 489 Ensure there are spaces between the fields in the header
  https://github.com/Colvars/colvars/pull/489 (@HanatoK)

- 487 Use map of output streams, and return references to its elements
  https://github.com/Colvars/colvars/pull/487 (@giacomofiorin, @jhenin)

- 486 Remember first step of moving restraint
  https://github.com/Colvars/colvars/pull/486 (@jhenin)

- 485 Add decoupling option for moving restraints
  https://github.com/Colvars/colvars/pull/485 (@jhenin)

- 483 Update Lepton via patching procedure
  https://github.com/Colvars/colvars/pull/483 (@giacomofiorin)

- 481 Make file-reading operations of input data abstractable
  https://github.com/Colvars/colvars/pull/481 (@giacomofiorin)

Authors: @akohlmey, @giacomofiorin, @HanatoK, @jhenin

lib/colvars/colvarcomp_gpath.cpp

@@ -12,6 +12,7 @@
 #include <cmath>
 #include <cstdlib>
 #include <limits>
+#include <fstream>
 
 #include "colvarmodule.h"
 #include "colvarvalue.h"
@@ -426,9 +427,8 @@ colvar::CVBasedPath::CVBasedPath(std::string const &conf): cvc(conf) {
     std::string path_filename;
     get_keyval(conf, "pathFile", path_filename);
     cvm::log(std::string("Reading path file: ") + path_filename + std::string("\n"));
-    std::ifstream ifs_path(path_filename);
-    if (!ifs_path.is_open()) {
-        cvm::error("Error: failed to open path file.\n");
+    auto &ifs_path = cvm::main()->proxy->input_stream(path_filename);
+    if (!ifs_path) {
         return;
     }
     std::string line;
@@ -459,6 +459,7 @@ colvar::CVBasedPath::CVBasedPath(std::string const &conf): cvc(conf) {
             ++total_reference_frames;
         }
     }
+    cvm::main()->proxy->close_input_stream(path_filename);
     if (total_reference_frames <= 1) {
 	cvm::error("Error: there is only 1 or 0 reference frame, which doesn't constitute a path.\n");
         return;