Fix modified libraries not being upgraded (#1734)

This commit removes checks to prevent modified libraries from being upgraded.

Originally intended to prevent accidental data loss of in-development libraries
the safe guard may prevent updates in production environments unintentionally.

It is not clear which mechanism modifies files on disk, but users have been
reporting untouched libraries from not upgrading for this reason, repetitively.

Author: deathaxe

package_control/package_manager.py

@@ -1238,22 +1238,6 @@ def install_library(self, lib):
                     )
                 return True
 
-            _, modified_ris = installed_library.dist_info.verify_files(missing_ok=True)
-            modified_paths = {mri.absolute_path for mri in modified_ris}
-            if modified_paths:
-                console_write(
-                    '''
-                    Unable to upgrade library "%s" for Python %s because files on disk have been modified:
-                      %s
-                    ''',
-                    (
-                        lib.name,
-                        lib.python_version,
-                        '\n  '.join(sorted(map(sys_path.shortpath, modified_paths), key=lambda s: s.lower()))
-                    )
-                )
-                return False
-
         lib_path = sys_path.lib_paths()[lib.python_version]
         tmp_dir = sys_path.longpath(tempfile.mkdtemp(''))
         tmp_library_dir = os.path.join(tmp_dir, lib.name)