lift/framework

Delegate equals comparison in Record to Field

Bump sbt and Scala 2.12/13 minor versions

These are set independently of the top-level Scala version builds. That
could probably use some refactoring, but it will have to wait for
another time.

2.13 incremental

This is an incremental setup based on work by @arashi01 that allows
for only certain modules to have 2.13 builds enabled. As of now, these
are almost all modules except for lift-json-scalaz7, lift-mapper,
lift-squeryl-record, lift-mongodb, and lift-mongodb-record.

Build-related updates include:
- Version bumps for specs2, sbt, scala-xml, scala-parser-combinators,
  and scalatest.
- Proper travis builds for 2.13.
- A deliberate version-bump strategy of “minimum needed to compile”. It
  felt like further bumping should be a separate thread.

In Scala 2.13, scalap started no longer reporting method parameters
under `MethodSymbol.children`. This broke the ability of lift-json to
compare method parameter types for class constructors, and therefore
broke the ability to find constructors that matched an extracting JSON
structure.

This commit introduces a separate method, `paramSymbolsFor`, to manage
method parameter lookup explicitly, without referencing
`MethodSymbol.children`. Relevant calls are replaced with calls to
`paramSymbolsFor`.

When LiftSessionSpec became a class instead of a singleton, access to
the constructors for the spec's helper comet actors started failing
during reflective instantiation. The comet actors now live in a
singleton again, which is imported into the spec class. The state
variables that are used in the space also live in the singleton, so they
are accessible from the helper actors. The wildcard import allows the
rest of the spec to operate unchanged.

JDK 11/12 have an inaccessible `Helpers` class in
`java.util.concurrent`. In lift-utill's `Schedule` class, a reference to
`Helpers` in the context of a wildcard `java.util.concurrent._` import
is leading the compiler to try to resolve the inaccessible `Helpers` class
instead of the package-local `net.liftweb.util.Helpers`.

This commit explicitly imports `Helpers` and `Helpers.TimeSpan` to sidestep
this issue.

Scala 2.13's singleton body evaluation semantics have changed, leading
to a failure to discover fragments inside a singleton spec (see
etorreborre/specs2#757).

There was some sort of build stall happening in Travis here.

In Scala 2.12, Javadoc comments weren't handled properly by scaladoc.
This is now fixed, so the limited Javadocs needed in Scala can be built
on 2.12 as well.

Before, ++<scala-version> ran as an independent command from `test`,
which essentially meant "switch all modules that CAN be switched to this
Scala version, then build all modules on their selected version", which
could mean you were building a 2.12 module during the 2.13 build. The
new formulation runs one command, `++<scala-version> test`, which limits
the `test` command to only modules that have the given Scala version
available.

Note that travis will currently fail on 2.13 as there are no projects
marked as compatible with 2.13.

One superficial placeholder argument bit the 2.13 compiler insists on,
and one move of `option2Box` and `box2Option` to their own
lower-priority implicits trait that is mixed into `BoxTrait`. This
allows for proper resolution of the `box2IterableOnce` implicit as
higher priority than the `box2Option` implicit when calling `flatten` on
a `Seq[Box[T]]`.

Where possible, avoid any dependencies that would require additional
upgrade work. Those can be pursued separately. There's a little extra
visibility into this due to parallel but incomplete work that's been
done to bump as many modules to 2.13 as possible, even though not all of
those bumps are ready for publishing.

Use a handy trick by @arashi01 to only specify the specs2 version once.

Co-authored-by: Ali Rashid <ali.r@thezanzibarcompany.com>

No modules build on Scala 2.13 yet, but setting a module to build will
simply involve overriding crossScalaVersions for it. The current default
is still 2.12, until a majority of modules are building on 2.13, or
until all of them are -- to be determined.

Bump build to scala 2.11.12 and see what happens

Fix snapshot builds

This PR should fix our snapshot building on
master. It will:

* Fix doc generation by fixing up our api
  mappings override for scala-xml
* Disable publishing from jdk11 and jdk12 so
  we don't cause surprises to folks expecting
  Java 8 builds