Stop loading the context in the constructor if it hasn't been provided.
There is no need to load it by default. We should lazily load it when it
is required.

There is an edge case whereby redis will fail
to accept connections on the first try but
retrying the connection seems to make it work

Included in this commit:
* Retry functionality in the session init

Conflicts:
	theme/boost/scss/moodle/modules.scss

The core_completion_get_activities_completion_status was getting the
progress for all users on the course called, and then discarding all
the records but one.

This change ensures that only progress for the user we are interested in
is retrieved from the database.

This has a side benefit of removing a full table scan from the query
finding the users inside the get_progress_all() method.

If the file does not have Unix line endings then the regular expression
in oci_native_moodle_database::attempt_oci_package_install() does
not split it correctly.

This leads to an invalid package being created in Oracle.

The .gitattribute file changes for oci_native_moodle_package.sql
force it to have Unix style line endings when the branch is checked
out and the file does not already exist.

The file has been modified so that the Unix style line endings are
applied even if the file already exists, for example when pulling in
this change to an existing branch.