Add forgotten abort() method of the Upgrader trampoline class, and allow
getErrors() not to crash if not upgrading

SLAs can be marked transient. When a ticket is assigned to a transient SLA
and it is transferred to a department or help topic having a default SLA,
the SLA will change to the SLA of the new department or help topic. This
process can continue as long as the ticket has a transient SLA assigned.
Once a non-transient SLA is assigned to the ticket, the SLA will no longer
change automatically. Thereafter, the SLA can only be manually changed.

on line 14 of settings-pages.inc.php the section: <a href="pages"> should read: <a href="pages.php">

Spelling, grammar and readability in upgrader documents
  - Tweaked spelling, grammar and wording to make the text of the upgrader
    pages more readable.
Fixed spelling regression
  - Higly —> Highly
Spelling and readability fixes for /include/class.* files
  - Fixed some spelling mistakes
A couple more spelling/readability fixes.
  - More fixes

Allow the installation to use the same streams config and schema signatures
as the migrater

Allow the install to install mulitple database streams

Allow `streams.cfg` to be implied as 'core', which will default to only
upgrading the core osTicket stream.

Use signature to describe snapshots rather than md5

This patch allows the upgrader to upgrade multiple database update
'streams'. The main stream is renamed to 'core' to reflect changes made
to the config class. This will significantly ease customizations
requiring database customizations, and will make plugins requiring
database changes possible.

- Handle decoding large base64 encoded attachments better
- Avoid transcoding from one charset to the same
- Avoid encoding attachments without a declared charset

When creating tickets, ensure that data which should not contain leading or
trailing whitespace is trimmed and validated accordingly

 - Supported pages: landing, offline, thank-you and other

If the body of an email message is written and encoded with an unrecognized
charset (like 'iso', for instance), then use the original text, assumed to
be 8-bit encoded. This patch will create idiosyncrasies, where text might be
transcoded to utf-8 incorrectly, but it should eliminate instances where
email message bodies are missing due to incorrect charset labels.

Looks like a long standing, yet-to-be-fixed PHP bug, where
zlib.output_compression can result in the output buffer not completely being
flushed. This is especially critical for downloads where the tail of the
file might be lost.

https://bugs.php.net/bug.php?id=19436

This will allow setting something in the session and having that value
override the value from the database. If ->persist() is called for a given
key, a following ->get() will result in the session persisted value being
returned. ->set() will still save the value in the database.

This is mostly useful for last-mile scenarios (and future plugins) that need
to affect the configuration of the system without altering the data in the
configuration table.

This allows another signal condition to the connection, so that, in addition
to the (sub) class, another check can be made before the signal is delivered
to the connected callable

- timezone_offset was dropped from the config table at 1.7-dpr1
- upgrader: only apply five patches in one request
- upgrader: fix readPatchInfo to work correctly
- session: support migrating from 1.6 (again)
- config: support migrating from 1.6 (fallback)
- config: no default for 'isonline' setting
- config: fix SQL whitespace issue for schema signature fallbacks
- config: hash 1.6 versions in the schema signature lookup
- upgrader: fix logging bug in attachment migration

Allow (a subset of) the configuration to also be saved in the session to
make session-backed data more consistent and compatible with up-and-coming
multi-site setups.

Attachment settings were merged into ticket settings
SMTPSpoofing feature was moved to per-email rather than global

Change the config table from a column-based table to a key-value table
with namespacing. This allows several parts of osTicket to store their
respective configurations in the same table without requiring database
structure updates

'namespace' is reserved in PHP

Add log error param flag