changes required to allow replacing the obsolete __conda_version__ in conda-rdkit (#1644)

* - changes which allow replacing the obsolete __conda_version__

* - Reverted CMakeLists.txt
- Reverted Code/cmake/Modules/RDKitUtils.cmake
- Reverted (i.e., removed) Code/cmake/Modules/RDKitVersion.cmake
- Moved to Conda subdir and adapted pkg_version.py

* - Removing debugging printouts

* - renamed Conda to build_support

build_support/pkg_version.py

@@ -0,0 +1,72 @@
+from __future__ import print_function
+import os
+import re
+from datetime import datetime
+from setuptools import setup
+
+pkg_version = ''
+src_dir = os.path.realpath(__file__)
+have_src_dir = os.path.isfile(src_dir)
+i = 0
+while (i < 2 and have_src_dir):
+  i += 1
+  src_dir = os.path.dirname(src_dir)
+  have_src_dir = os.path.isdir(src_dir)
+if (not have_src_dir):
+  raise OSError('Could not find SRC_DIR, got: ' + str(src_dir))
+# parse root CMakeLists.txt and Code/cmake/Modules/RDKitUtils.cmake
+root_cmakelists_path = os.path.join(src_dir, 'CMakeLists.txt')
+rdkitutils_path = os.path.join(src_dir, 'Code', 'cmake',
+  'Modules', 'RDKitUtils.cmake')
+
+var_dict = {}
+for file in (root_cmakelists_path, rdkitutils_path):
+  with open(file, 'rt') as hnd:
+    # vars we want to read
+    var_set = set(['RDKit_Year', 'RDKit_Month', 'RDKit_Revision',
+      'RDKit_ABI', 'RDKit_RELEASENAME'])
+    line = hnd.readline()
+    while (line):
+      # is this an uncommented set command?
+      m = re.match('^\s*set\s*\((\w+)\s*\"(.*)\"\s*\)',
+        line, re.IGNORECASE)
+      # if it is
+      if (m is not None):
+        # extract the var name
+        var_name = m.group(1)
+        if (var_name in var_set):
+          # if the var name is in the vars we want to read
+          var_value = m.group(2)
+          keepLooping = True
+          while (keepLooping):
+            # recursively replace variables we already found
+            m = re.match('^.*\${(\w+)}', var_value)
+            keepLooping = (m is not None)
+            if (keepLooping):
+              v = var_dict.get(m.group(1))
+              # if the variable is not defined, remove
+              # the preceding dot
+              eat_dot = 0
+              if (v is None):
+                v = ''
+                eat_dot = 1
+              # replace variable name with its value
+              s = m.start(1) - (2 + eat_dot)
+              e = m.end(1) + 1
+              var_value = var_value[:s] + v + var_value[e:]
+          # assign variable value and keep parsing
+          var_dict[var_name] = var_value
+      line = hnd.readline()
+d = datetime.today().strftime('%Y%m%d')
+rdkitVersion = var_dict.get('RDKit_RELEASENAME')
+if (rdkitVersion is not None):
+  if rdkitVersion.endswith('.dev1'):
+    pkg_version = rdkitVersion[:-1] + d
+  else:
+    pkg_version = rdkitVersion
+else:
+  # if extracting rdkitVersion somehow failed, use the date
+    pkg_version = d
+
+print('rdkitVersion:', pkg_version)
+setup(rdkitVersion = pkg_version)